Use __BIONIC__ instead of ANDROID to check for bionic

ANDROID is set when building in an Android source tree, even when
building for the host architecture.  Check against __BIONIC__ instead,
which is only set when building against Bionic libc.

Bug: 190084016
Test: mmma USE_HOST_MUSL=true external/libdrm
Change-Id: Ic1e22c32b45195dbed775721436536abd02ae664
1 file changed