More compile fixes and Makefile changes

Re-introduce preprocessor assembly (CPP_ASSEMBLY) for misc toolchains (clang)

More clang defines on Makefile, specifically for preprocessor assembly

Fix custom defines on ASMFLAGS, fix end cake screen with EXTERNAL_DATA

Workaround for defines on macOS asm macros, M_PI safeguard and NO_PIE proper make define

Renamed some Make print output, added EXTERNAL_DATA print output and more target names