Simplify the compiler flags for the android test projects

These parts aren't performance critical, thus overriding the
compiler optimization flags (and arm instruction mode) isn't
necessary.
Update the generic 32 bit arm linux cpu feature detection to support 64 bit kernels

On 64 bit kernels, /proc/cpuinfo doesn't list the same old features
as on 32 bit kernels, since most of them are mandatory on 64 bit arm
systems, see [1] for details.

If running a 32 bit arm binary on such a kernel, we need to detect
the features slightly differently, either by using other names
listed in the Features field on these devices, by checking the
"CPU architecture" field and always enabling these if the architecture
is >= 8, or by parsing /proc/self/auxv or using the getauxval function.

[1] http://marc.info/?l=linux-arm-kernel&m=139087240101974
fix error judgment on return value in pauseframe
check each WriteBlockResidualCavlc to avoid overflow
Merge pull request #1047 from mstorsjo/cpufeatures-armv8

Update the generic 32 bit arm linux cpu feature detection to support 64 bit kernels
Merge pull request #1050 from ruil2/update_param

fix error judgment on return value in pauseframe
Merge pull request #1051 from ruil2/overflow_check

check each WriteBlockResidualCavlc to avoid overflow
Merge pull request #1044 from mstorsjo/android-cleanup-compiler-flags

Simplify the compiler flags for the android test projects