parser: Assign value without if-statement

This avoids an if-statement, because effectively it does nothing.  And,
for example, binary artifact generated by GCC with -O2 optimization
settings does not contain that if-statement -- the code just uses the
hprefix->name field explicitly.

No functional changes intended.

Signed-off-by: Ruslan Garipov <ruslanngaripov@gmail.com>

parser.c

@@ -8804,10 +8804,7 @@ xmlParseAttribute2(xmlParserCtxtPtr ctxt,
         return(hname);
     }
     name = hname.name;
-    if (hprefix->name != NULL)
-        prefix = hprefix->name;
-    else
-        prefix = NULL;
+    prefix = hprefix->name;
 
     /*
      * get the type if needed