kernel: use .ONESHELL to speed up processing of many kmod-* packages

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@43024 3c298f89-4303-0410-b956-a3cf2f4a3e73

package/kernel/linux/Makefile

@@ -18,6 +18,7 @@ PKG_LICENSE:=GPLv2
 PKG_LICENSE_FILES:=
 
 export SHELL:=/bin/sh
+.ONESHELL:
 
 include $(INCLUDE_DIR)/package.mk