clk: iproc: Remove __init marking on iproc_pll_clk_setup()

Now that this function is called from driver probe routines, it
needs to drop the __init marking because it isn't just called
from init code.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Sandeep Tripathy <sandeep.tripathy@broadcom.com>
Cc: Anup Patel <anup.patel@broadcom.com>
Cc: Ray Jui <ray.jui@broadcom.com>
Cc: Scott Branden <scott.branden@broadcom.com>
Fixes: 654cdd32 ("clk: bcm: Add clocks for Stingray SOC")
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>