[ARM] Remove clk_use()/clk_unuse()

[ARM] Remove clk_use()/clk_unuse()

It seems that clk_use() and clk_unuse() are additional complexity
which isn't required anymore.  Remove them from the clock framework
to avoid the additional confusion which they cause, and update all
ARM machine types except for OMAP.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>