add sse2 and atomic build flags

[YangMame]

No description provided.

[YangMame]

the reason: xbmc/xbmc#21743
RISC-V lack 8-bit and 16-bit atomic instructions, and
ARM/MIPS/PPC lack 64-bit atomic instruction.

GCC is supposed to convert these atomics via masking and shifting
like LLVM, which means anything that wants to use these instructions
needs the link option -latomic.

In this patch, we will try to detect if 8-bit, 64-bit atomic instructions exist,
otherwise the atomic library will append to the DEPLIBS list.