crate-fetch: Switch to version contained in bitbake

This avoids various sstate fetch errors from weird silent failures in the sstate
archive testing code caused by lack of srcrev support in the crate fetcher.

(From OE-Core rev: 8205668a339946974b4460cf1ca7e6e7a645479b)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/cargo_common.bbclass

@@ -9,7 +9,6 @@
 ##
 
 # add crate fetch support
-inherit crate-fetch
 inherit rust-common
 
 # Where we download our registry and dependencies to

meta/classes/crate-fetch.bbclass

@@ -1,28 +0,0 @@
-#
-# crate-fetch class
-#
-# Registers 'crate' method for Bitbake fetch2.
-#
-# Adds support for following format in recipe SRC_URI:
-# crate://<packagename>/<version>
-#
-
-def import_crate(d):
-    import crate
-    if not getattr(crate, 'imported', False):
-        bb.fetch2.methods.append(crate.Crate())
-        crate.imported = True
-
-python crate_import_handler() {
-    import_crate(d)
-}
-
-addhandler crate_import_handler
-crate_import_handler[eventmask] = "bb.event.RecipePreFinalise"
-
-def crate_get_srcrev(d):
-    import_crate(d)
-    return bb.fetch2.get_srcrev(d)
-
-# Override SRCPV to make sure it imports the fetcher first
-SRCPV = "${@crate_get_srcrev(d)}"