emulators/ppsspp: drop unused GL deps after 34a5259f5126

=>> Checking shared library dependencies

• 0x0000000000000001 NEEDED Shared library: [libGL.so.1] 0x0000000000000001 NEEDED Shared library: [libGLEW.so.2]
• 0x0000000000000001 NEEDED Shared library: [libGLU.so.1]

+ 0x0000000000000001 NEEDED Shared library: [libOpenGL.so.0]

0x0000000000000001 NEEDED               Shared library: [libSDL2-2.0.so.0]

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