[X86][Assembler] Allow %eip as a register in 32-bit mode for .cfi directives.

This basically reverts a change made in r336217, but improves the text of the error message for not allowing IP-relative addressing in 32-bit mode.

Fixes PR38826.

Patch by Iain Sandoe.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@341512 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed