Renames views/player to views/music_player (#18)

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## Description
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The MP3 player was named `player` in view context. It had multiple
meanings.
Although probably not perfect (since it only plays MP3 files, this
renames it to `music_player`.

## Motivation and Context
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<!--- If it fixes/closes/resolves an open issue, please link to the
issue here -->
It could be confusing otherwise.

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## Screenshots
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## Types of changes
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the boxes that apply: -->
- [ ] Improvement (non-breaking change that adds a new feature)
- [ ] Bug fix (fixes an issue)
- [ ] Breaking change (breaking change)
- [ ] Config and build (change in the configuration and build system,
has no impact on code or features)

## Checklist:
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- [ ] My code follows the code style of this project.
- [ ] My change requires a change to the documentation.
- [ ] I have updated the documentation accordingly.
- [ ] I have added tests to cover my changes.
- [ ] All new and existing tests passed.

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Makefile

@@ -36,7 +36,7 @@ SRCS = \
 	menu/views/fragments/fragments.c \
 	menu/views/fragments/widgets.c \
 	menu/views/load.c \
-	menu/views/player.c \
+	menu/views/music_player.c \
 	menu/views/startup.c \
 	menu/views/system_info.c \
 	utils/fs.c

src/menu/menu.c

@@ -112,8 +112,8 @@ void menu_run (boot_params_t *boot_params) {
                     view_system_info_display(menu, display);
                     break;
 
-                case MENU_MODE_PLAYER:
-                    view_player_display(menu, display);
+                case MENU_MODE_MUSIC_PLAYER:
+                    view_music_player_display(menu, display);
                     break;
 
                 case MENU_MODE_CREDITS:
@@ -158,8 +158,8 @@ void menu_run (boot_params_t *boot_params) {
                         view_system_info_init(menu);
                         break;
 
-                    case MENU_MODE_PLAYER:
-                        view_player_init(menu);
+                    case MENU_MODE_MUSIC_PLAYER:
+                        view_music_player_init(menu);
                         break;
 
                     case MENU_MODE_CREDITS:

src/menu/menu_state.h

@@ -24,7 +24,7 @@ typedef enum {
     MENU_MODE_BROWSER,
     MENU_MODE_FILE_INFO,
     MENU_MODE_SYSTEM_INFO,
-    MENU_MODE_PLAYER,
+    MENU_MODE_MUSIC_PLAYER,
     MENU_MODE_CREDITS,
     MENU_MODE_LOAD,
     MENU_MODE_ERROR,

src/menu/views/browser.c

@@ -209,7 +209,7 @@ static void process (menu_t *menu) {
                 menu->next_mode = MENU_MODE_LOAD;
                 break;
             case ENTRY_TYPE_MUSIC:
-                menu->next_mode = MENU_MODE_PLAYER;
+                menu->next_mode = MENU_MODE_MUSIC_PLAYER;
                 break;
             default:
                 menu->next_mode = MENU_MODE_FILE_INFO;

src/menu/views/music_player.c

@@ -124,7 +124,7 @@ static void draw (menu_t *menu, surface_t *d) {
 }
 
 
-void view_player_init (menu_t *menu) {
+void view_music_player_init (menu_t *menu) {
     mp3player_err_t error;
 
     unmute_counter = 0;
@@ -151,10 +151,10 @@ void view_player_init (menu_t *menu) {
     path_free(path);
 }
 
-void view_player_display (menu_t *menu, surface_t *display) {
+void view_music_player_display (menu_t *menu, surface_t *display) {
     process(menu);
     draw(menu, display);
-    if (menu->next_mode != MENU_MODE_PLAYER) {
+    if (menu->next_mode != MENU_MODE_MUSIC_PLAYER) {
         mp3player_deinit();
     }
 }

src/menu/views/views.h

@@ -29,8 +29,8 @@ void view_system_info_display (menu_t *menu, surface_t *display);
 void view_file_info_init (menu_t *menu);
 void view_file_info_display (menu_t *menu, surface_t *display);
 
-void view_player_init (menu_t *menu);
-void view_player_display (menu_t *menu, surface_t *display);
+void view_music_player_init (menu_t *menu);
+void view_music_player_display (menu_t *menu, surface_t *display);
 
 void view_credits_init (menu_t *menu);
 void view_credits_display (menu_t *menu, surface_t *display);