rs6000: Delete mention of -mabi={no-,}spe in the documentation

The option no longer exists.


	* doc/invoke.texi (RS/6000 and PowerPC Options): Delete mention of
	-mabi=spe and -mabi=no-spe.

From-SVN: r261323

gcc/ChangeLog

+2018-06-08  Segher Boessenkool  <segher@kernel.crashing.org>
+
+	* doc/invoke.texi (RS/6000 and PowerPC Options): Delete mention of
+	-mabi=spe and -mabi=no-spe.
+
 2018-06-08  Martin Liska  <mliska@suse.cz>
 
 	* ipa-pure-const.c (propagate_pure_const): Use ::get at places

gcc/doc/invoke.texi

@@ -23845,8 +23845,8 @@ SVR4 ABI)@.
 @item -mabi=@var{abi-type}
 @opindex mabi
 Extend the current ABI with a particular extension, or remove such extension.
-Valid values are @samp{altivec}, @samp{no-altivec}, @samp{spe},
-@samp{no-spe}, @samp{ibmlongdouble}, @samp{ieeelongdouble},
+Valid values are @samp{altivec}, @samp{no-altivec},
+@samp{ibmlongdouble}, @samp{ieeelongdouble},
 @samp{elfv1}, @samp{elfv2}@.
 
 @item -mabi=ibmlongdouble