rules.mk: add TARGET_INIT_PATH toplevel variables

Add a new variable TARGET_INIT_PATH which holds the default $PATH variable
value configured in menuconfig.

Signed-off-by: Jo-Philipp Wich <jow@openwrt.org>

rules.mk

@@ -117,6 +117,8 @@ BUILD_LOG_DIR:=$(TOPDIR)/logs
 PKG_INFO_DIR := $(STAGING_DIR)/pkginfo
 
 TARGET_PATH:=$(subst $(space),:,$(filter-out .,$(filter-out ./,$(subst :,$(space),$(PATH)))))
+TARGET_INIT_PATH:=$(call qstrip,$(CONFIG_TARGET_INIT_PATH))
+TARGET_INIT_PATH:=$(if $(TARGET_INIT_PATH),$(TARGET_INIT_PATH),/usr/sbin:/sbin:/usr/bin:/bin)
 TARGET_CFLAGS:=$(TARGET_OPTIMIZATION)$(if $(CONFIG_DEBUG), -g3) $(EXTRA_OPTIMIZATION)
 TARGET_CXXFLAGS = $(TARGET_CFLAGS)
 TARGET_ASFLAGS_DEFAULT = $(TARGET_CFLAGS)