Linux x86 nss/lib/freebl/mpi/mpi_x86.s confusion of mp_digit size

see <https://groups.google.com/forum/#!topic/mozilla.dev.security/n16bQj4qZHc>

Change-Id: I6635d187b29d6b50fbccaf3f4c29d72660fcaa5e

external/nss/UnpackedTarball_nss.mk

@@ -16,6 +16,7 @@ $(eval $(call gb_UnpackedTarball_add_patches,nss,\
 	external/nss/nss.aix.patch \
 	external/nss/nss-3.13.5-zlib-werror.patch \
 	external/nss/nss_macosx.patch \
+	external/nss/nss-linux-x86.patch.0 \
 	$(if $(filter WNTMSC,$(OS)$(COM)),external/nss/nss.windows.patch) \
 	$(if $(filter WNTGCC,$(OS)$(COM)),external/nss/nspr-4.9-build.patch.3 \
 		external/nss/nss-3.13.3-build.patch.3 \

external/nss/nss-linux-x86.patch.0

+--- nss/lib/freebl/Makefile
++++ nss/lib/freebl/Makefile
+@@ -195,6 +195,7 @@
+ ifeq ($(CPU_ARCH),x86)
+     ASFILES  = mpi_x86.s
+     DEFINES += -DMP_ASSEMBLY_MULTIPLY -DMP_ASSEMBLY_SQUARE 
++    DEFINES += -DMP_USE_UINT_DIGIT
+     DEFINES += -DMP_ASSEMBLY_DIV_2DX1D
+     DEFINES += -DMP_CHAR_STORE_SLOW -DMP_IS_LITTLE_ENDIAN
+     # The floating point ECC code doesn't work on Linux x86 (bug 311432).