Add automated build via Cirrus CI (#929)

This change enables automated build via Cirrus CI.

.cirrus.yml

@@ -0,0 +1,16 @@
+snes9xgx_gamecube-wii_task:
+  container:
+    image: devkitpro/devkitppc
+  
+  update_script:
+    - sudo dkp-pacman -Sy --noconfirm
+    - sudo dkp-pacman -S libfat-ogc libogc --noconfirm
+  
+  setup_script:
+    - cp -r /tmp/cirrus-ci-build/buildtools/libfreetype.a /opt/devkitpro/portlibs/ppc/lib/
+    - cp -r /tmp/cirrus-ci-build/buildtools/libfreetype.la /opt/devkitpro/portlibs/ppc/lib/
+    
+  compile_script:
+    - make -j3
+  build_artifacts:
+    path: "executables/*"

buildtools/libfreetype.la

@@ -0,0 +1,41 @@
+# libfreetype.la - a libtool library file
+# Generated by ltmain.sh (GNU libtool) 2.2.6b
+#
+# Please DO NOT delete this file!
+# It is necessary for linking the library.
+
+# The name that we can dlopen(3).
+dlname=''
+
+# Names of this library.
+library_names=''
+
+# The name of the static archive.
+old_library='libfreetype.a'
+
+# Linker flags that can not go in dependency_libs.
+inherited_linker_flags=''
+
+# Libraries that this one depends upon.
+dependency_libs=' -L$DEVKITPRO/ppc/lib -lz'
+
+# Names of additional weak libraries provided by this library
+weak_library_names=''
+
+# Version information for libfreetype.
+current=12
+age=6
+revision=0
+
+# Is this an already installed library?
+installed=yes
+
+# Should we warn about portability when linking against -modules?
+shouldnotlink=no
+
+# Files to dlopen/dlpreopen
+dlopen=''
+dlpreopen=''
+
+# Directory that this library needs to be installed in:
+libdir='$DEVKITPRO/portlibs/ppc/lib'