Update FVP model version to 11.12.35

Updated FVP model version to 11.12.35 as per latest
stable release communicated by the model team and updated
'hercules' and 'zeus' models as below:

1. Changed 'hercules' model script name to 'cortex-a78x4'.
2. Changed 'zeus' model script name to 'neoverse-v1x4'.
3. Changed 'hercules' model from 'FVP_Base_Herculesx4'
   to 'FVP_Base_Cortex-A78x4'.
4. Changed 'zeus' model from 'FVP_Base_Zeusx4' to
   'FVP_Base_Neoverse-V1x4'.

Also, retained the model version for 'FVP_RD_E1_edge' as
11.9.41

Change-Id: I4cd0d29070a7cf76b7652788a539ab4f5480bd40
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
diff --git a/utils.sh b/utils.sh
index 7c63dc9..92d4aa3 100644
--- a/utils.sh
+++ b/utils.sh
@@ -290,8 +290,8 @@
 jenkins_url="${jenkins_url:-https://ci.trustedfirmware.org/}"
 
 # Model revisions
-model_version="${model_version:-11.9}"
-model_build="${model_build:-41}"
+model_version="${model_version:-11.12}"
+model_build="${model_build:-35}"
 model_flavour="${model_flavour:-Linux64_GCC-6.4}"
 
 # Model snapshots from filer are not normally not accessible from developer