sdk: filter out main on GIT_BRANCH parsing

Branch named main was never filter out on parsing the GIT_BRANCH define.

Add main to the name of branch that should be filtered.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
(cherry picked from commit 0338dd4)

Author: Ansuel

target/sdk/Makefile

@@ -41,7 +41,7 @@ SDK_DIRS = \
 GIT_URL:=$(shell git config --get remote.origin.url 2>/dev/null)
 GIT_URL:=$(if $(CONFIG_BUILDBOT),$(filter git://% http://% https://%,$(GIT_URL)),$(GIT_URL))
 GIT_COMMIT:=$(shell git rev-parse HEAD 2>/dev/null)
-GIT_BRANCH:=$(filter-out master HEAD,$(shell git rev-parse --abbrev-ref HEAD 2>/dev/null))
+GIT_BRANCH:=$(filter-out master main HEAD,$(shell git rev-parse --abbrev-ref HEAD 2>/dev/null))
 GIT_TAGNAME:=$(shell git show-ref --tags --dereference 2>/dev/null | sed -ne '/^$(GIT_COMMIT) / { s|^.*/||; s|\^.*||; p }')
 
 BASE_FEED:=$(if $(GIT_URL),src-git-full base $(GIT_URL)$(if $(GIT_BRANCH),;$(GIT_BRANCH),$(if $(GIT_TAGNAME),;$(GIT_TAGNAME))))