clk: mediatek: reset: Support nonsequence base offsets of reset registers

clk: mediatek: reset: Support nonsequence base offsets of reset registers

The bank offsets are not serial for all reset registers.
For example, there are five infra reset banks for MT8192: 0x120, 0x130,
0x140, 0x150 and 0x730.

To support this,
- Change reg_ofs to rst_bank_ofs which is a pointer to base offsets of
  the reset register.
- Add a new define RST_NR_PER_BANK to define reset number for each
  reset bank.

Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Tested-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Link: https://lore.kernel.org/r/20220523093346.28493-8-rex-bc.chen@mediatek.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>