Don't adjust PATH and LIB unless MOZ_MEMORY is set

config/autoconf.mk.in

@@ -557,10 +557,12 @@ WIN32_REDIST_DIR = @WIN32_REDIST_DIR@
 WIN32_CRT_SRC_DIR = @WIN32_CRT_SRC_DIR@
 WIN32_CUSTOM_CRT_DIR = @WIN32_CUSTOM_CRT_DIR@
 # These are for custom CRT building
+ifdef MOZ_MEMORY
 ifneq (,$(WIN32_CRT_SRC_DIR)$(WIN32_CUSTOM_CRT_DIR))
 export LIB = @MOZ_LIB@
 export PATH = @MOZ_PATH@
 endif
+endif
 # python options.
 MOZ_PYTHON_EXTENSIONS = @MOZ_PYTHON_EXTENSIONS@
 MOZ_PYTHON = @MOZ_PYTHON@