toolchain/glibc: fixup the libm.so linker script too

Add it to the existing list to fix it up.

Found by mold:
toolchain-x86_64_gcc-12.2.0_glibc/lib/libm.so:4: GROUP ( /lib/libm.so.6  AS_NEEDED ( /lib/libmvec.so.1 ) )
                                                         ^ library not found: /lib/libm.so.6

Signed-off-by: Andre Heider <[email protected]>

toolchain/glibc/Makefile

@@ -20,7 +20,7 @@ define Host/Install
 		install
 	( cd $(TOOLCHAIN_DIR) ; \
 		for d in lib usr/lib ; do \
-		  for f in libc.so libpthread.so libgcc_s.so ; do \
+		  for f in libc.so libm.so libpthread.so libgcc_s.so ; do \
 		    if [ -f $$$$d/$$$$f -a ! -L $$$$d/$$$$f ] ; then \
 		      $(SED) 's,/usr/lib/,,g;s,/lib/,,g' $$$$d/$$$$f ; \
 		    fi \