ANDROID: bazel: Fix dtc header dependencies

As dtc compiles util.c, which includes util.h and version_non_gen.h
(or version_gen.h upstream), the cc_binary should list those
dependencies explicitly so that a change in them triggers a rebuild.

Furthermore, dtc also depends on dtc.h and srcpos.h, which are only
found as dependencies by Bazel through the overkill glob(["*.h"]) header
list of dtc_gen so list them explicitly here so that that cc_library can
be dropped.

Introduce the UTILS list to DRY the build file.

Test: bazel build //:dtc
Change-Id: I32076c65b60820dc91f6dc84c3ee3cad310c1db5
diff --git a/BUILD.bazel b/BUILD.bazel
index 439621d..8a65ba8 100644
--- a/BUILD.bazel
+++ b/BUILD.bazel
@@ -55,18 +55,25 @@
     deps = [":libfdt"],
 )
 
+UTILS = [
+    "util.c",
+    "util.h",
+    "version_non_gen.h",
+]
+
 cc_binary(
     name = "dtc",
-    srcs = [
+    srcs = UTILS + [
         "checks.c",
         "data.c",
         "dtc.c",
+        "dtc.h",
         "flattree.c",
         "fstree.c",
         "livetree.c",
         "srcpos.c",
+        "srcpos.h",
         "treesource.c",
-        "util.c",
     ],
     copts = COPTS,
     defines = ["NO_YAML"],
@@ -78,11 +85,8 @@
 
 cc_binary(
     name = "fdtget",
-    srcs = [
+    srcs = UTILS + [
         "fdtget.c",
-        "util.c",
-        "util.h",
-        "version_non_gen.h",
     ],
     copts = COPTS,
     defines = ["NO_YAML"],
@@ -91,11 +95,8 @@
 
 cc_binary(
     name = "fdtput",
-    srcs = [
+    srcs = UTILS + [
         "fdtput.c",
-        "util.c",
-        "util.h",
-        "version_non_gen.h",
     ],
     copts = COPTS,
     defines = ["NO_YAML"],
@@ -104,11 +105,8 @@
 
 cc_binary(
     name = "fdtdump",
-    srcs = [
+    srcs = UTILS + [
         "fdtdump.c",
-        "util.c",
-        "util.h",
-        "version_non_gen.h",
     ],
     copts = COPTS,
     defines = ["NO_YAML"],
@@ -117,11 +115,8 @@
 
 cc_binary(
     name = "fdtoverlay",
-    srcs = [
+    srcs = UTILS + [
         "fdtoverlay.c",
-        "util.c",
-        "util.h",
-        "version_non_gen.h",
     ],
     copts = COPTS,
     defines = ["NO_YAML"],