msm: kgsl: Enable perfcounter save/restore for A4XX

3XX targets have the ability to save the contents of most performance
counters on power down and to restore the values on power up so as
lessen the impact of sleep and nap on profiilng applications. Bring
this support to 4XX as well and support the larger field
of counters available on 4XX targets.

Change-Id: Ic0dedbad00adad16cadb75ed5d3a49761e045107
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>