libast: rm unused fmtversion function (re: 15c248f)

It formats a version number as defined by magicid.h, which was
removed in the referenced commit.

Author: McDutchie

src/lib/libast/Mamfile

@@ -1721,13 +1721,6 @@ make install virtual
 			exec - compile %{<}
 		done
 
-		make fmtversion.o
-			make string/fmtversion.c
-				prev include/ast.h
-			done
-			exec - compile %{<}
-		done
-
 		make strelapsed.o
 			make string/strelapsed.c
 				prev include/ast.h

src/lib/libast/include/ast.h

@@ -351,7 +351,6 @@ extern char*		fmtscale(Sfulong_t, int);
 extern char*		fmtsignal(int);
 extern char*		fmttime(const char*, time_t);
 extern char*		fmtuid(int);
-extern char*		fmtversion(unsigned long);
 extern void*		memdup(const void*, size_t);
 extern unsigned int	memhash(const void*, int);
 extern unsigned long	memsum(const void*, int, unsigned long);