ARM: sa1111: remove some redundant definitions

SA1111_VBASE, SA1111_p2v, SA1111_v2p, _SA1111, SA1111_ADDR_WIDTH,
SA1111_ADDR_MASK, and SA1111_DMA_ADDR are not used anywhere in the
kernel, so remove these redundant definitions.

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