Removed "-fkeep-inline-functions" from CFLAGS, since it now has no effect

except to generate spurious warnings about a system header <sys/param.h>
having some inline functions (the bswap family).  This backs out the main
part of rev.1.5 (which was the only part left).  The problem fixed by
rev.1.5 of the Makefile went away in rev.1.5 of ../common/crtbegin.c
when the references to do_ctors() and do_dtors() in the latter were moved
from inline asm to C code.

This leaves the problem that implementation details cause warnings.

Discussed with:	jdp

lib/csu/amd64/Makefile

@@ -5,7 +5,7 @@
 SRCS=		crt1.c crti.S crtn.S
 OBJS=		${SRCS:N*.h:R:S/$/.o/g}
 OBJS+=		gcrt1.o
-CFLAGS+=	-elf -Wall -fkeep-inline-functions \
+CFLAGS+=	-elf -Wall \
 		-I${.CURDIR}/../common \
 		-I${.CURDIR}/../../libc/include
 LDFLAGS+=	-elf

lib/csu/i386-elf/Makefile

@@ -5,7 +5,7 @@
 SRCS=		crt1.c crti.S crtn.S
 OBJS=		${SRCS:N*.h:R:S/$/.o/g}
 OBJS+=		gcrt1.o
-CFLAGS+=	-elf -Wall -fkeep-inline-functions \
+CFLAGS+=	-elf -Wall \
 		-I${.CURDIR}/../common \
 		-I${.CURDIR}/../../libc/include
 LDFLAGS+=	-elf