Fixes build error on ARM:

if armv5tel-redhat-linux-gnueabi-gcc -DLOCALEDIR=\"\" -DHAVE_CONFIG_H   -include ../config.h -I../include -fsigned-char -fomit-frame-pointer   -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -DUSE_TTY_GROUP -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -march=armv5te -MT umount.o -MD -MP -MF ".deps/umount.Tpo" -c -o umount.o umount.c; \
        then mv -f ".deps/umount.Tpo" ".deps/umount.Po"; else rm -f ".deps/umount.Tpo"; exit 1; fi
umount.c:32: error: static declaration of 'umount2' follows non-static declaration
/usr/include/sys/mount.h:115: error: previous declaration of 'umount2' was here
umount.c:34: error: expected declaration specifiers or '...' before 'umount2'
umount.c:34: error: expected declaration specifiers or '...' before 'path'
umount.c:34: error: expected declaration specifiers or '...' before 'flags'
umount.c:34: warning: data definition has no type or storage class
umount.c:34: warning: type defaults to 'int' in declaration of '_syscall2'
make[2]: *** [umount.o] Error 1
make[2]: Leaving directory `/usr/src/redhat/BUILD/util-linux-2.13-pre6/mount'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/usr/src/redhat/BUILD/util-linux-2.13-pre6'
make: *** [all] Error 2


--- util-linux/mount/umount.c.orig	2006-12-05 00:55:57.000000000 +0000
+++ util-linux/mount/umount.c	2006-12-05 00:56:02.000000000 +0000
@@ -20,7 +20,7 @@
 #include "env.h"
 #include "nls.h"
 
-#if defined(MNT_FORCE) && !defined(__sparc__) && !defined(__arm__)
+#if defined(MNT_FORCE) && !defined(__sparc__)
 /* Interesting ... it seems libc knows about MNT_FORCE and presumably
    about umount2 as well -- need not do anything */
 #else /* MNT_FORCE */