bug 300335 allocate enough memory

patch by Andrew Schultz <ajschult@verizon.net> r+sr=mscott a=bsmedberg

extensions/spellcheck/myspell/src/csutil.cpp

@@ -212,7 +212,7 @@ struct cs_info * get_current_cs(const char * es) {
   if (NS_FAILED(rv))
     return nsnull;
 
-  ccs = (struct cs_info *) malloc(0xff * sizeof(cs_info));
+  ccs = (struct cs_info *) malloc(256 * sizeof(cs_info));
 
   PRInt32 charLength = 256;
   PRInt32 uniLength = 512;