uml: fix string exporting on UML/i386

In 2.6.23-rc1, i386 fiddled its string support such that UML started getting
undefined references from modules.  The UML asm/string.h was including the
i386 string.h, which defined __HAVE_ARCH_STR*, but the corresponding
implementations weren't being pulled in.

This is fixed by adding arch/i386/lib/string.h to the list of host
architecture files to be pulled in to UML.

A complication is that the libc exports file assumed that the generic strlen
and strstr weren't in use (i.e.  __HAVE_ARCH_STR is defined), then they aren't
exported.  This is untrue for strlen, which is exported in either case, so
this logic is not needed.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/um/sys-i386/Makefile

@@ -4,7 +4,7 @@ obj-y = bug.o bugs.o checksum.o delay.o fault.o ksyms.o ldt.o ptrace.o \
 
 obj-$(CONFIG_MODE_SKAS) += stub.o stub_segv.o
 
-subarch-obj-y = lib/bitops.o lib/semaphore.o
+subarch-obj-y = lib/bitops.o lib/semaphore.o lib/string.o
 subarch-obj-$(CONFIG_HIGHMEM) += mm/highmem.o
 subarch-obj-$(CONFIG_MODULES) += kernel/module.o