habanalabs: unify code for memory access from debugfs

Currently each asic version implements 4 callbacks:
'debugfs_{read32/write32/read64/write64}'
There is a lot of code duplication among the different
callbacks of all asic versions.
This patch unify the code in order to avoid the code
duplication by iterating the pci_mem_region array
in hl_device and use its fields instead of macros.

Signed-off-by: Dafna Hirschfeld <dhirschfeld@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>