The x86-64 architecture mandates support for MMX and SSE2, so we don't
need to tell that the compiler generates them. They're implied.
This could serve to determine that the user specified no -march= or -m
flags that affect the architecture on the CMAKE_CXX_FLAGS, but fails if
the compiler does that on its own for this particular target. For
example, both for Android and macOS, the minimum feature set is SSSE3
for 32-bit and SSE4.1 for 64-bit.
Change-Id: I76216ced393445a4ae2dfffd172a94b17e8a9a37
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>
77e89dcce4