x86-asm-for-linus-v5.7

 - Remove last remaining calls to exception_enter/exception_exit() and
   simplify the entry code some more.

 - Remove force_iret()

 - Add support for "Fast Short Rep Mov", which is available starting with
   Ice Lake Intel CPUs - and make the x86 assembly version of memmove()
   use REP MOV for all sizes when FSRM is available.

 - Micro-optimize/simplify the 32-bit boot code a bit.

 - Use a more future-proof SYSRET instruction mnemonic

Signed-off-by: Ingo Molnar <mingo@kernel.org>