Remove old files from SDL external

They were already removed in SDL upstream but the update mechanism did
not remove them in this repository.

They were causing build failures when the SDL external was used.

externals/SDL/Xcode/SDL/hidapi/Info.plist

@@ -1,22 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
-<plist version="1.0">
-<dict>
-	<key>CFBundleDevelopmentRegion</key>
-	<string>$(DEVELOPMENT_LANGUAGE)</string>
-	<key>CFBundleExecutable</key>
-	<string>$(EXECUTABLE_NAME)</string>
-	<key>CFBundleIdentifier</key>
-	<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
-	<key>CFBundleInfoDictionaryVersion</key>
-	<string>6.0</string>
-	<key>CFBundleName</key>
-	<string>$(PRODUCT_NAME)</string>
-	<key>CFBundlePackageType</key>
-	<string>$(PRODUCT_BUNDLE_PACKAGE_TYPE)</string>
-	<key>CFBundleShortVersionString</key>
-	<string>$(CURRENT_PROJECT_VERSION)</string>
-	<key>CFBundleVersion</key>
-	<string>$(CURRENT_PROJECT_VERSION)</string>
-</dict>
-</plist>