In this test we use GL_BGRA + GL_UNSIGNED_BYTE. However, the probe
function receives two 4-byte values to compare, expected and
observed. This is wrong as the correct way to compare
array_of_bytes (GL_UNSIGNED_BYTE) in an endian-safe way is by comparing
memory (and not values).

This patch fixes this bug by changing the function to receive two
pointers instead of values. It also corrects the way the expected values
are constructed to be in endian-safe way for array-of-bytes

This fixes the test in llvmpipe, softpipe and r600g in big-endian machine.

v2: Changed initialization of expected results to be more clear
v3: Changed printing of results to display individual components
v4: Changed some indentation

Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
v2: Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>