In Zfa, MINI/MAXI -> MINM/MAXM

@mehnadnerd pointed out that the trailing 'I' implies 'immediate'.

AR doesn't want the long MINIMUM/MAXIMUM names I had proposed;
instead, we are simply replacing the 'I' with 'M'.

src/zfa.tex

@@ -119,17 +119,17 @@ \section{Load-Immediate Instructions}
 
 \section{Minimum and Maximum Instructions}
 
-The FMINI.S and FMAXI.S instructions are defined like the FMIN.S and FMAX.S
+The FMINM.S and FMAXM.S instructions are defined like the FMIN.S and FMAX.S
 instructions, except that if either input is NaN, the result is the
 canonical NaN.
 
-If the D extension is implemented, FMINI.D and FMAXI.D instructions are
+If the D extension is implemented, FMINM.D and FMAXM.D instructions are
 analogously defined to operate on double-precision numbers.
 
-If the Zfh extension is implemented, FMINI.H and FMAXI.H instructions are
+If the Zfh extension is implemented, FMINM.H and FMAXM.H instructions are
 analogously defined to operate on half-precision numbers.
 
-If the Q extension is implemented, FMINI.Q and FMAXI.Q instructions are
+If the Q extension is implemented, FMINM.Q and FMAXM.Q instructions are
 analogously defined to operate on quad-precision numbers.
 
 These instructions are encoded like their FMIN and FMAX counterparts, but