YASM accepts labels without colons, but NASM issues warnings.

This is more consistent with the way we handle C #includes and
it simplifies the build system.

This is necessary to allow refactoring some x86util macros with cpuflags.

We cannot clip to INT_MAX because that value cannot be exactly
represented by a float value and ends up overflowing during conversion
anyway. We need to use a slightly smaller float value, which ends up
with slightly inaccurate results for samples which clip or nearly clip,
but it is close enough. Using doubles as intermediates in the conversion
would be more accurate, but it takes about twice as much time.

Signed-off-by: Luca Barbato <lu_zero@gentoo.org>

This separates code relying on inline from that relying on external
assembly and fixes instances where the coalesced check was incorrect.

nasm prints a warning if the colon is missing.

Signed-off-by: Mans Rullgard <mans@mansr.com>

Removes a false dependency on existing contents of the 2nd dst register,
giving better performance for OOE.

Adds optimized functions for mixing 3 through 8 input channels to 1 and 2
output channels in fltp or s16p format with flt coeffs.

Changed to match the number of parameters in conv_func_interleave(), which is
how they are called. The change isn't strictly necessary because the 4th
parameter is not used, but the code is clearer if they match.