clk: ux500: fix erroneous bit assignment

Due to a typo or similar, the peripheral group 2 clock 11
gate was set to bit 1 instead of bit 11. We need to fix this
to be able to set the correct enable bit in the device tree:
when trying to correct the bit assignment in the device tree,
the system would hang.

Cc: Mike Turquette <mturquette@linaro.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>