scripts/check-patches-apply.py: Fix strip value for refs with a slash

For refs with a slash in them, such as the arm64 refs 'for-next/core'
and 'for-next/fixes', the tarball will be formatted like:

  for-next/core/Makefile
  for-next/core/arch/...

which causes an incorrect layout with the current value of 1 and patches
that would normally apply correctly fail to do so. The strip value for
the above scenario needs to be 2 to allow the patches to apply
correctly. Use the length of the list created by splitting on slashes as
the strip value so that the layout is consistent for patch application.

Signed-off-by: Nathan Chancellor <[email protected]>

Author: nathanchance

scripts/check-patches-apply.py

@@ -52,7 +52,7 @@
         # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git ->
         # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/snapshot/linux-master.tar.gz
         tarball_url = f"{args.repo}/snapshot/{base_repo}-{args.ref}.tar.gz"
-        strip = 1
+        strip = len(args.ref.split('/'))
     elif 'googlesource.com' in args.repo:
         tarball_url = f"{args.repo}/+archive/refs/heads/{args.ref}.tar.gz"
         strip = 0