[X86] Fix a bug when calculating the ldtilecfg insertion points.

The BB we initialized the ldtilecfg is special. We don't need to check
if its predecessor BBs need to insert ldtilecfg for calls.

We reused the flag HasCallBeforeAMX, so that the predecessors won't be
added to CfgNeedInsert.

This case happens only when the entry BB is in a loop. We need to hoist
the first tile config point out of the loop in future.

Reviewed By: LuoYuanke

Differential Revision: https://reviews.llvm.org/D98845