gdb/aarch64: record/replay support for RPRFM, PRFM (reg), PRFUM

The PRFM (register) instruction variant was unsupported. This is added
along with RPRFM and PRFUM.

No testcase has been added as these are hint instructions which don't
modify registers/memory.

The full testsuite was done on aarch64-none-linux-gnu without RPRFM.
The gdb.arch and gdb.reverse tests were run on Shrinkwrap with RPRFM
support.

Approved-By: Luis Machado <luis.machado.foss@gmail.com>