Update gsutil cryptography wheel to 2.9.2

While I'm here, change to a more concise way of spelling the platform
string.

Bug: 1179513
Change-Id: Ibb9bd69fb00e66332f8af73154f4615c20efb2b6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2703228
Auto-Submit: Owen Rodley <orodley@chromium.org>
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
Reviewed-by: Edward Lesmes <ehmaldonado@chromium.org>

gsutil.vpython

@@ -35,8 +35,8 @@ wheel: <
 ##
 
 wheel: <
-  name: "infra/python/wheels/cryptography/${platform}_${py_python}_${py_abi}"
-  version: "version:2.0.3"
+  name: "infra/python/wheels/cryptography/${vpython_platform}"
+  version: "version:2.9.2"
 >
 
 wheel: <
@@ -44,18 +44,13 @@ wheel: <
   version: "version:1.4.3"
 >
 
-wheel: <
-  name: "infra/python/wheels/asn1crypto-py2_py3"
-  version: "version:1.0.1"
->
-
 wheel: <
   name: "infra/python/wheels/enum34-py2"
   version: "version:1.1.6"
 >
 
 wheel: <
-  name: "infra/python/wheels/cffi/${platform}_${py_python}_${py_abi}"
+  name: "infra/python/wheels/cffi/${vpython_platform}"
   version: "version:1.10.0"
 >