libregex-re2: Added conditional switch to arm mode instead of thumb for devices that don't support thumb2. Tested on heroc with armv6j.
libregex-re2: Added conditional switch to arm mode instead of thumb for
devices that don't support thumb2. Tested on heroc with armv6j.

Change-Id: I9ccda93983d4aee220467bc5aa89846bcabcce23

ThirdProject/android_external_regex-re2,ThirdProject/android_external_regex-re2,ThirdProject/android_external_regex-re2,CyanogenMod/android_external_regex-re2,ThirdProject/android_external_regex-re2,ThirdProject/android_external_regex-re2,CyanogenMod/android_external_regex-re2,CyanogenMod/android_external_regex-re2,CyanogenMod/android_external_regex-re2,CyanogenMod/android_external_regex-re2