r600g: set endianess of 16/32-bit buffers according to do_endian_swap

r600g: set endianess of 16/32-bit buffers according to do_endian_swap

This patch modifies r600_colorformat_endian_swap(), so for 16-bit and for
32-bit buffers, the endianess configuration will be determined not only
by the color/texture format, but also by the do_endian_swap parameter.

The only exception is for array formats, which are always set to not do
swapping, because for them gallium sets an alias based on the machine's
endianess.

v4:
V_0280A0_COLOR_16_16 and V_0280A0_COLOR_16_16_FLOAT should be set to
8IN16 because the bytes inside need to be swapped even for array formats.

Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Cc: "11.1 11.2" <mesa-stable@lists.freedesktop.org>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>