[MLIR] Normalize usage of intrinsics_gen

Portions of MLIR which depend on LLVMIR generally need to depend on
intrinsics_gen, to ensure that tablegen'd header files from LLVM are built
first.  Without this, we get errors, typically about llvm/IR/Attributes.inc
not being found.

Note that previously the Linalg Dialect depended on intrinsics_gen, but it
doesn't need to, since it doesn't use LLVMIR.

Differential Revision: https://reviews.llvm.org/D79389