build: arm: cosmetics: Place all OBJS declarations in alphabetical order

Signed-off-by: Martin Storsjö <martin@martin.st>
build: cosmetics: Place unconditional before conditional OBJS lines

Signed-off-by: Martin Storsjö <martin@martin.st>
arm: Only build the FFT init files if FFT is enabled

This fixes build errors in cases where FFT is disabled.

Signed-off-by: Martin Storsjö <martin@martin.st>
arm: Don't unconditionally build dsputil files

Signed-off-by: Martin Storsjö <martin@martin.st>
arm: Include hpeldsp_neon.o if h264qpel is enabled

A few of the h264qpel neon functions are shared with other
hpeldsp functions in this file.

This fixes standalone compilation of the h264 decoder on arm.

Signed-off-by: Martin Storsjö <martin@martin.st>