Bumped version of p4c in p4 tools script

Needed to fix bug seen when compiling spgw.p4

Change-Id: I2f6d06bdd7755e0819c8f1dc91d3746f922089cb
diff --git a/tools/dev/bin/onos-setup-p4-dev b/tools/dev/bin/onos-setup-p4-dev
index 476f715..b44f915 100755
--- a/tools/dev/bin/onos-setup-p4-dev
+++ b/tools/dev/bin/onos-setup-p4-dev
@@ -17,7 +17,7 @@
 BUILD_DIR=~/p4tools
 BMV2_COMMIT="d930fa2818d8ed71f3bf36eaf3f3687d9b68184f"
 PI_COMMIT="13d611a9c655938676ebcde2bd5653b461f46ca7"
-P4C_COMMIT="03da20f95cce7b785c6c25745c7eeec2a14a7bf4"
+P4C_COMMIT="cb8f118ed2861986cd20a3e34f18ee7ae3862233"
 PROTOBUF_COMMIT="tags/v3.2.0"
 GRPC_COMMIT="tags/v1.3.2"