[build][arch][arm] squelch additional LIBGCC and compile flags echoing
[build][arch][arm] squelch additional LIBGCC and compile flags echoing

Already printed elsewhere, quiet down the build a bit.

hollanderic/lkstuff,littlekernel/lk,travisg/lk,travisg/lk,hollanderic/lkstuff,travisg/lk,littlekernel/lk,littlekernel/lk,hollanderic/lkstuff,littlekernel/lk,travisg/lk,hollanderic/lkstuff