build: kernel: build arm kernel modules with -fno-pic

With androidkernel (androideabi) toolchains, -fpic is enabled by default.
At least on my 3.4 arm kernel, this causes an issue with kernel modules:
"Unknown symbol _GLOBAL_OFFSET_TABLE_".

On traditional armeabi toolchains, -fpic is not enabled, resulting in working
kernel modules; let's follow that here.

Change-Id: I3058b5213b34bdde9bb9d744563c7d55cd42d2a5