Switch to the hermetic toybox gzip.

Bug: http://b/288169261
Test: treehugger
Change-Id: I52832fc5bae23c9cd5f7b1329576c86ac09a92ee
diff --git a/Android.bp b/Android.bp
index 1de0238..293b578 100644
--- a/Android.bp
+++ b/Android.bp
@@ -79,7 +79,6 @@
     ],
     required: [
         "lz4",
-        "minigzip",
         "mkbootfs",
         "mkbootimg",
         "toybox",
diff --git a/repack_bootimg.py b/repack_bootimg.py
index 93c28f9..a322a68 100755
--- a/repack_bootimg.py
+++ b/repack_bootimg.py
@@ -104,7 +104,7 @@
         # trying lz4 first.
         for compression_type, compression_util in [
             (RamdiskFormat.LZ4, 'lz4'),
-            (RamdiskFormat.GZIP, 'minigzip')]:
+            (RamdiskFormat.GZIP, 'gzip')]:
 
             # Command arguments:
             #   -d: decompression
@@ -141,7 +141,7 @@
         """
         compression_cmd = ['lz4', '-l', '-12', '--favor-decSpeed']
         if self._ramdisk_format == RamdiskFormat.GZIP:
-            compression_cmd = ['minigzip']
+            compression_cmd = ['gzip']
 
         print('Repacking ramdisk, which might take a few seconds ...')