[X86] Remove some isel patterns for X86ISD::SELECTS that specifically looked...

[X86] Remove some isel patterns for X86ISD::SELECTS that specifically looked for the v1i1 mask to have come from a scalar_to_vector from GR8.

We have patterns for SELECTS that top at v1i1 and we have a pattern for (v1i1 (scalar_to_vector GR8)). The patterns being removed here do the same thing as the two other patterns combined so there is no need for them.

llvm-svn: 336305