staging/xgifb: Simplify XGI_SetSeqRegs

Since SR[0] in the (readonly) XGI330_StandTable is always 0x01 we can
skip or'ing with 0x01 and make the code simpler by removing the if
statements.

Since this function is the only user of the XGI330_StandTable we can
also include the unconditional |= 0x20 into the input data and move the
assignment to SR1 into the loop, which I prefer to start at 0.

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>