tcg: Use correct trap number for page faults on *BSD systems

tcg: Use correct trap number for page faults on *BSD systems

The trap number for a page fault on BSD systems is T_PAGEFLT
not 0xe -- 0xe is used by Linux and represents the intel hardware
trap vector. The BSD kernels, however, translate this to T_PAGEFLT
in their Xpage, Xtrap0e, Xtrap14, etc fault handlers. This is true
for i386 and x86_64, though the name of the trap hanlder can very
on the flavor of BSD. As far as I can tell, Linux doesn't provide
a define for this value. Invent a new one (PAGE_FAULT_TRAP) and
use it instead to avoid uglier ifdefs.

Signed-off-by: Mark Johnston <markj@FreeBSD.org>
Signed-off-by: Juergen Lock <nox@FreeBSD.org>
[ Rework to avoid ifdefs and expand it to i386 ]
Signed-off-by: Warner Losh <imp@bsdimp.com>
Message-Id: <20210625045707.84534-3-imp@bsdimp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>