crypto: qat - rename and relocate timer logic

crypto: qat - rename and relocate timer logic

Rename adf_gen4_timer.c to adf_timer.c and adf_gen4_timer.h to
adf_timer.h to make the files generation-agnostic. This includes
renaming the start() and stop() timer APIs and macro definitions
to be generic, allowing for reuse across different device
generations.
This does not introduce any functional changes.

Signed-off-by: George Abraham P <george.abraham.p@intel.com>
Reviewed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>