[source] include: relax umask check

[LEDE Commits]

jow pushed a commit to source.git, branch master:
https://git.lede-project.org/be6f836841300fc6e9c401946ad4e5384e178f89

commit be6f836841300fc6e9c401946ad4e5384e178f89
Author: Jo-Philipp Wich <jo at mein.io>
AuthorDate: Tue Oct 4 14:05:56 2016 +0200

    include: relax umask check
    
    For now we only want to ensure that the group permission mask is permissive
    enough to not clobber required permissions on the rootfs, so allow less
    strict masks as well.
    
    Signed-off-by: Jo-Philipp Wich <jo at mein.io>
---
 include/prereq-build.mk | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/prereq-build.mk b/include/prereq-build.mk
index c3b88db..4a0509a 100644
--- a/include/prereq-build.mk
+++ b/include/prereq-build.mk
@@ -26,7 +26,7 @@ $(eval $(call TestHostCommand,case-sensitive-fs, \
 
 $(eval $(call TestHostCommand,proper-umask, \
 	Please build with umask 022 - other values produce broken packages, \
-	umask | grep -xF 0022))
+	umask | grep -xE 00[012][012]))
 
 $(eval $(call SetupHostCommand,gcc, \
 	Please install the GNU C Compiler (gcc), \