ARM: i.MX1 clk: Add missing clocks

This patch adds missing clocks for mpll_gate, spll_gate, uart3_gate,
ssi2_gate and brom_gate. As an additional this fixes incorrect bit
position for dma_gate clock.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>