cpu/allwinner/a10: Refactor API for gating clocks to peripherals

Rather than having to track which bit in which register should be
cleared or set to gate or ungate the clock to a certain peripheral,
provide a simplified enum which encodes the register and bit. This
change comes with a function which decodes the enum and gates/ungates
the clock.

This also removes the register-dependent bitmasks for APB0 and APB1
gating registers.

Change-Id: Ib3ca16e54eb37eadc3ceb88f4ccc497829ac34bc
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Reviewed-on: http://review.coreboot.org/4571
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
4 files changed