building on Mac (BigSur, AppleSilicon)

[akita11]

I'm trying to install graywolf on Mac (BigSur), and succeeded with some modification on source codes.
Here is my modification points, and I hope this will help someone to install graywolf on Mac with xcode compiler sets, where some of them would be a fixed in original sources.

• prepare Homebrew
• install cmake & libx11 by "brew install".
• edit CMakeLists.txt at below line to avoid type-related errors and to set include/link path

---

SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS}
-DSIZEOF_VOID_P=${SIZEOF_VOID_P_BITS}
-Wno-implicit-function-declaration -Wno-return-type -Wno-format -I /usr/local/include -L /usr/local/lib")

• on Mac(M1), getCompileDate() doesn't seem to work, so commended it out in program.c.
• in genrows/draw.c, type specification "VOID" doesn't work, so delete it.

[breadnbeer]

I also had to remove *strcat() declaration in realpath.c.
(Big Sur, Intel chip)