Fix SDC_LOCAL_GITREPO for relative paths

SDC_LOCAL_GITREPO will not do what you want (most likely) if used
with a relative path - it worked only with an absolute one.

This commit fixes this but it adds a new requirement: 'realpath';
which should be on any system as it is part of the coreutils and
similar package sets.

Issue-ID: SDC-2553

Signed-off-by: Petr Ospalý <p.ospaly@partner.samsung.com>
Change-Id: I2d79252cb315538997c91b754acb59f52469df00
diff --git a/scripts/sdc/setup_sdc_for_sanity.sh b/scripts/sdc/setup_sdc_for_sanity.sh
index 2d644c3..dba6eb5 100644
--- a/scripts/sdc/setup_sdc_for_sanity.sh
+++ b/scripts/sdc/setup_sdc_for_sanity.sh
@@ -50,6 +50,7 @@
 
 cd "${WORKSPACE}/data/clone"
 if using_local_images && [ -n "$SDC_LOCAL_GITREPO" ] ; then
+    SDC_LOCAL_GITREPO=$(realpath "$SDC_LOCAL_GITREPO")
     if [ -d "$SDC_LOCAL_GITREPO" ] ; then
         rm -rf ./sdc
         cp -a "$SDC_LOCAL_GITREPO" ./sdc