Make libcompat a static only library.

Since functions will come and go from libcompat as they are deprecated
it makes no sense to build a shared library out of it as it will change.

Based on freedback from Terry and Jonas on the mailing lists.

lib/libcompat/Makefile

@@ -3,6 +3,7 @@
 LIB=compat
 CFLAGS+=-DLIBC_SCCS -DSYSLIBC_SCCS
 AINC=	-I${.CURDIR}/../libc/${MACHINE}
+NOPIC=
 
 .PATH:	${.CURDIR}/4.1/${MACHINE} ${.CURDIR}/4.1 \
 	${.CURDIR}/4.3/${MACHINE} ${.CURDIR}/4.3 \