gas: Update 80387 floating point 's' suffix

Update 80387 floating point 's' suffix to read:

  * Integer constructors are '.word', '.long' or '.int', and '.quad'
     for the 16-, 32-, and 64-bit integer formats.  The corresponding
     instruction mnemonic suffixes are 's' (short), 'l' (long), and 'q'
     (quad).

instead of 's' (single).

	PR gas/27106
	* doc/c-i386.texi: Update 80387 floating point 's' suffix