[X86] Replace selectScalarSSELoad ComplexPattern with PatFrags to handle the 3 types...

[X86] Replace selectScalarSSELoad ComplexPattern with PatFrags to handle the 3 types of loads we currently match.

This ensures we create mem operands for these instructions fixing PR45949.

Unfortunately, it increases the size of X86GenDAGISel.inc, but some dag
combine canonicalization could reduce the types of load we need to match.