[X86] Support CFE flags for APX features (#74199)

Positive options: -mapx-features=<comma-separated-features>
Negative options: -mno-apx-features=<comma-separated-features>

-m[no-]apx-features is designed to be able to control separate APX
features.

Besides, we also support the flag -m[no-]apxf, which can be used like an
alias of -m[no-]apx-features=< all APX features covered by CPUID APX_F>

Behaviour when positive and negative options are used together:

For boolean flags, the last one wins

-mapxf   -mno-apxf   -> -mno-apxf
-mno-apxf   -mapxf   -> -mapxf

For flags that take a set as arguments, it sets the mask by order of the
flags

-mapx-features=egpr,ndd  -mno-apx-features=egpr  ->   -egpr,+ndd
-mapx-features=egpr  -mno-apx-features=egpr,ndd  ->   -egpr,-ndd
-mno-apx-features=egpr  -mapx-features=egpr,ndd  ->   +egpr,+ndd
-mno-apx-features=egpr,ndd  -mapx-features=egpr  ->   -ndd,+egpr

The design is aligned with gcc
https://gcc.gnu.org/pipermail/gcc-patches/2023-August/628905.html