[bazel] Add "gazelle" target to bazel/Makefile

This is easier for me to find, as I more often work in the infra repo.

Change-Id: I93d02299604c8b502f89576ada7597a8443b24e8
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/1049956
Auto-Submit: Eric Boren <borenet@google.com>
Reviewed-by: Kaylee Lubick <kjlubick@google.com>
Commit-Queue: Eric Boren <borenet@google.com>
Commit-Queue: Kaylee Lubick <kjlubick@google.com>

bazel/Makefile

diff --git a/bazel/Makefile b/bazel/Makefile
index e10f5a7..e8e47fa 100644
--- a/bazel/Makefile
+++ b/bazel/Makefile
@@ -6,6 +6,9 @@
        bazel/device_specific_configs bazel/exporter bazel/deps_parser tools/gpu/gl/interface \
 			 tools/testrunners/common/make_tarball tools/testrunners/common/android/adb_test_runner
 
+.PHONY: gazelle
+gazelle: generate_go
+
 .PHONY: generate_cmake
 generate_cmake:
 	cd .. && bazelisk build //bazel/exporter_tool && ${EXPORTER_TOOL} \