Fixed ldim alignment bug in core2 gemm ukernel.

Details:
- Fixed a bug in the dunnington/core2 gemm micro-kernels that resulted in
  a segmentation fault if a column-stored matrix's starting address was
  aligned, but its leading dimension was such that its second column was
  unaligned. Basically, the micro-kernel was assuming that aligned load
  instructions were safe when they actually were not. An extra condition
  that checks the alignment of cs_c (ie: the leading dimension in the
  column storage case) has now been added. Thanks to Michael Lehn for
  reporting this bug.