mksh does not require special LDFLAGS/CPPFLAGS

tools/mksh/Makefile

@@ -18,7 +18,6 @@ install: ${STAGING_HOST_DIR}/usr/bin/mksh
 
 $(WRKBUILD)/.compiled: ${WRKDIST}/.prepared
 	cd ${WRKBUILD} && CC='${CC_FOR_BUILD}' CFLAGS='${CFLAGS_FOR_BUILD}' \
-	    CPPFLAGS='${CPPFLAGS_FOR_BUILD}' LDFLAGS='${LDFLAGS_FOR_BUILD}' \
 	    HAVE_CAN_FSTACKPROTECTORALL=0 \
 	    TARGET_OS=Linux ${BASH} ${WRKSRC}/Build.sh -Q -r -c lto
 	touch $@