clk: ingenic: support PLLs with no bypass bit

The second PLL of the JZ4770 does not have a bypass bit.
This commit makes it possible to support it with the current common CGU
code.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Maarten ter Huurne <maarten@treewalker.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/18479/


Signed-off-by: James Hogan <jhogan@kernel.org>