getparameter: remove dead code

Coverity CID 1061126. 'parse' will always be non-NULL here.

src/tool_getparam.c

@@ -437,12 +437,7 @@ ParameterError getparameter(char *flag,    /* f or -long-flag */
     /* we can loop here if we have multiple single-letters */
 
     if(!longopt) {
-      if(NULL != parse) {
-        letter = (char)*parse;
-      }
-      else {
-        letter = '\0';
-      }
+      letter = (char)*parse;
       subletter='\0';
     }
     else {