i386: Use SWI48DWI mode iterator for abs and maxmin [PR97873]

i386: Use SWI48DWI mode iterator for abs and maxmin [PR97873]

Generate special double mode sequence also for TImode on 64bit targets.

2020-11-22  Uroš Bizjak  <ubizjak@gmail.com>

	PR target/97873

gcc/
	* config/i386/i386.md (abs<mode>2): Use SWI48DWI mode iterator.
	(*abs<dwi>2_doubleword): Use DWIH mode iterator.

	(<maxmin:code><mode>3): Use SWI48DWI mode iterator.
	(*<maxmin:code><dwi>3_doubleword): Use DWIH mode iterator.

gcc/testsuite/
	* gcc.target/i386/pr97873-2.c: New test.