default compiler. This has two parts:
- Make sys/boot/pc98/boot2 always build with gcc for now, until we can
figure out a way to shrink it enough when building with clang.
- Since sys/boot/p98/cdboot uses .code16 directives, which are not yet
supported by clang's integrated assembler, use -no-integrated-as,
similar to sys/boot/i386/cdboot.
Reviewed by: nyan
MFC after: 1 week
GCC forwards the -N flag directly to ld. This flag is not documented and
not supported by (for example) Clang. Just use -Wl,-N.
Submitted by: Pawel Worach
