linux-advanced: Fix Kernel EXTRAVERSION for BR2_LINUX26_CUSTOM

Closes #1267

Signed-off-by: serj.kalichev <serj.kalichev@gmail.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

CHANGES

@@ -45,6 +45,7 @@
 	#1129: Bump memstat to 0.8 and migrate to Makefile.package.in
 	#1189: Wrong u-boot configuration name for integrator926 target
 	#1219: kernel headers not correctly installed into toolchain/staging
+	#1267: Wrong BR2_EXTRA_VERSION
 	#1273: BR2_INET_IPV6 does not enable IPv6 in pppd
 	#1303: Add librsync package
 	#1321: Busybox link fails due to lack of --sysroot option

target/linux/Config.in.advanced

@@ -263,7 +263,7 @@ config BR2_EXTRA_VERSION
 	default "$(BR2_KERNEL_RC_LEVEL)" if					BR2_KERNEL_ADD_RC_PATCH
 	default "$(BR2_KERNEL_GIT_LEVEL)" if					BR2_KERNEL_ADD_LATEST_SNAPSHOT
 	default "$(BR2_KERNEL_GIT_LEVEL)" if					BR2_KERNEL_ADD_SNAPSHOT
-	default	"$(BR2_CUSTOM_LINUX26_VERSION)" if				BR2_LINUX26_CUSTOM
+	default	"" if								BR2_LINUX26_CUSTOM
 endmenu
 
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