fix Osmocom_Sanitize build
The Osmocom_Sanitize build is failing at libosmocore.
Notably, ./configure --enable-sanitize works, but the way the Osmocom_Sanitize job builds with 'make CFLAGS+="stuff"' breaks the build cmdline, since it drops these: -O2 -g -msse3 -msse4.1.
Let's add the --enable-sanitize configure switch in every osmocom git repos (of interest) and include such build in the standard master HEAD as well as gerrit build jobs. Drop the Osmocom_Sanitize build entirely.
ml thread: http://lists.osmocom.org/pipermail/openbsc/2017-June/010821.html
add --enable-sanitize in libosmocore: http://git.osmocom.org/libosmocore/commit/?id=a23817622b28cb1969a73ffd36da501eb29b9cd7