nspr: Add LDFLAGS to TARGET_CC_ARCH to fix warning

nspr: Add LDFLAGS to TARGET_CC_ARCH to fix warning

WARNING: QA Issue: No GNU_HASH in the elf binary: 'armv7a-vfp-neon-mel-linux-gnueabi/nspr/4.10-r0/packages-split/nspr-dev/usr/lib/nspr/tests/formattm'
WARNING: QA Issue: No GNU_HASH in the elf binary: 'armv7a-vfp-neon-mel-linux-gnueabi/nspr/4.10-r0/packages-split/nspr-dev/usr/lib/nspr/tests/threads'
WARNING: QA Issue: No GNU_HASH in the elf binary: 'armv7a-vfp-neon-mel-linux-gnueabi/nspr/4.10-r0/packages-split/nspr-dev/usr/lib/nspr/tests/semaerr'
There are many QA Warnings thrown like the above for this recipe. This is observed for target imx6 sabrelite.

(From OE-Core rev: 98d9af299c6e110c7560f282f37f1f85c155213d)

Signed-off-by: Sujith H <Sujith_Haridasan@mentor.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>