ARMv6: Fix indentation in the composite macros
ARMv6: remove 1 instr per row in generate_composite_function

This knocks off one instruction per row. The effect is probably too small to
be measurable, but might as well be included. The second occurrence of this
sequence doesn't actually benefit at all, but is changed for consistency.

The saved instruction comes from combining the "and" inside the .if
statement with an earlier "tst". The "and" was normally needed, except
for in one special case, where bits 4-31 were all shifted off the top of
the register later on in preload_leading_step2, so we didn't care about
their values.

v4, Pekka Paalanen <pekka.paalanen@collabora.co.uk> :
	Remove "bits 0-3" from the comments, update patch summary, and
	augment message with Ben's suggestion.
lowlevel-blt-bench: over_reverse_n_8888 needs solid source

v4, Pekka Paalanen <pekka.paalanen@collabora.co.uk> :
	Split from "Add extra test to lowlevel-blt-bench and fix an
	existing one", new summary.
lowlevel-blt-bench: add in_reverse_8888_8888 test

in_reverse_8888_8888 is one of the more commonly used operations in the
cairo-perf-trace suite that hasn't been in lowlevel-blt-bench until now.

v4, Pekka Paalanen <pekka.paalanen@collabora.co.uk> :
	Split from "Add extra test to lowlevel-blt-bench and fix an
	existing one", new summary.