Both gnu as and clang treat lines starting with '#' as comments if they
aren't consumed by the C-style preprocessor.
Using '//' does not work with clang since comments are removed before
macro expansion.
This fixes building in PIC mode with gas. The examples in the gas
manual showed using a # here even though gas itself actually didn't
support that syntax (and the gas test suite only tests it without
the extra hash sign).
CC: libav-stable@libav.org
Signed-off-by: Martin Storsjö <martin@martin.st>
NEON and VFP are currently mandatory for all ARMv8 profiles. Both are
handled as extensions as far as cpuflags are concerned. This is
consistent with handling x86_64 which always has SSE2, but still
handles it as an extension.
