Removed parameter "Consecutive" from isLegalMaskedLoad() / isLegalMaskedStore().

Originally I planned to use the same interface for masked gather/scatter and set isConsecutive to "false" in this case.

Now I'm implementing masked gather/scatter and see that the interface is inconvenient. I want to add interfaces isLegalMaskedGather() / isLegalMaskedScatter() instead of using the "Consecutive" parameter in the existing interfaces.

Differential Revision: http://reviews.llvm.org/D13850

llvm-svn: 250686