external-toolchain: recognize uClibc 64 bits toolchains

With uClibc 64 bits toolchain, the dynamic loader is named
ld64-uClibc.so.0 and not ld-uClibc.so.0. So, this commit adjust the
uClibc detection code for external toolchains.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reviewed-by: Yann E. MORIN <yann.morin.1998@anciens.enib.fr>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

toolchain/external-toolchain/ext-tool.mk

@@ -216,7 +216,7 @@ check_uclibc_feature = \
 #
 check_uclibc = \
 	SYSROOT_DIR="$(strip $1)"; \
-	if ! test -f $${SYSROOT_DIR}/lib/ld-uClibc.so.* ; then \
+	if ! test -f $${SYSROOT_DIR}/lib/ld*-uClibc.so.* ; then \
 		echo "Incorrect selection of the C library"; \
 		exit -1; \
 	fi; \