Implement --no-fatal-warning for compatibility with newer ld
what ever order the options are passed to ld(1) the --no-fatal-warning always
disable --fatal-warning
MFi386: r275059, r275061, r275062 and r275191 (by rdivacky)

  Shrink boot2 by a couple more bytes.
Ignore more warnings with external gcc
Switch to the ARM unified assembly language as the clang integrated as only
supports it. Binutils supports it when the ".syntax unified" directive
is set.

Sponsored by:	ABT Systems Ltd
Merge remote-tracking branch 'freebsd/master' into hardened/current/master