clk: ux500: Fix prcmu clocks registration

In clk_reg_prcmu(), clk->hw.init field is assigned with a
reference local to clk_reg_prcmu() function.

This patch replaces references to clk->hw.init with calls
to __clk_get_name when called after clock registration.

This patch applies on top of v3.9-rc4.

Signed-off-by: Maxime Coquelin <maxime.coquelin@st.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
[mturquette@linaro.org: resolved trivial merge issues]