Add ED64 Plus (ED64P) build support (#33)

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## Description
The ED64 V1 Cart clones (commonly referred to as ED64 Plus) require a
different file name and are more feature limited. This PR adds them to
the build process.

## Motivation and Context
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issue here -->
Someone will add it, so it might as well be me.
Hopefully some more users of them will get on board with this project.

## How Has This Been Tested?
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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)
- [x] Config and build (change in the configuration and build system,
has no impact on code or features)

## Checklist:
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that apply. -->
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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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.github/workflows/build.yml

@@ -59,6 +59,12 @@ jobs:
           name: ED64
           path: ./output/OS64.v64
 
+      - name: Upload artifact (ED64P version)
+        uses: actions/upload-artifact@v3
+        with:
+          name: ED64P
+          path: ./output/OS64P.v64
+
       - name: Upload artifact (SC64 version)
         uses: actions/upload-artifact@v3
         with:

Makefile

@@ -94,6 +94,10 @@ ed64: $(BUILD_DIR)/$(PROJECT_NAME)_stripped.n64
 	$(shell cp $< $(OUTPUT_DIR)/OS64.v64)
 .PHONY: ed64
 
+ed64-clone: $(BUILD_DIR)/$(PROJECT_NAME)_stripped.n64
+	$(shell cp $< $(OUTPUT_DIR)/OS64P.v64)
+.PHONY: ed64-clone
+
 sc64: $(BUILD_DIR)/$(PROJECT_NAME)_stripped.n64
 	$(shell cp $< $(OUTPUT_DIR)/sc64menu.n64)
 .PHONY: sc64