Fixing Qt detection of CPU architecture, adding armv6l detection
Fixing Qt detection of CPU architecture, adding armv6l detection

Previously, compilation worked for all architectures at the
expense of the use of SSE2 instructions. The offending line
(where $$QMAKE_HOST.arch is checked) always returned true. This
is because $$QMAKE_HOST.arch was not read properly before the
equals() check, making the check return false. It was then not-ed
and returned true. Thus support for ARM was achieved because of
two errors cancelling eachother out, but negatively impacting
non-ARM processor performance.

This patch explicitly defines QMAKE_XCPUARCH = $$QMAKE_HOST.arch
before the equals check, removes the not on the equals() check,
and adds in a check for armv6l architecture CPUs as well.

magi-project/magi,magi-project/magi,magi-project/magi,magi-project/magi,magi-project/magi