ANDROID: update the kernel release format for GKI

The new kernel release format is: w.x.y-zz-k where,
  w.x.y are the current values
  zzz is the Android Release value
  k is the KMI Generation number

This allows one to identify the kernel module interface version using
`uname -r`. The KMI Generation number is used to identify any KMI
changes that occur after the KMI freeze. This should only occur in an
unlikely event that a security patch requires a KMI update.

Here is a local example:
  5.4.51-android12-0-00153-ga972f59040e4-dirty

Signed-off-by: Will McVicker <willmcvicker@google.com>
Bug: 159842160
Change-Id: I33f40e424ca967b85d810cdb12c6a2c58e4197b7
[willmcvicker: squash with commit 0c0d4177]