Remove superfluous whitespace.

src/hotspot/cpu/arm/arm.ad

@@ -979,7 +979,7 @@ const bool Matcher::match_rule_supported_vector(int opcode, int vlen, BasicType
   // e.g. Op_ vector nodes and other intrinsics while guarding with vlen
   bool ret_value = match_rule_supported(opcode) && vector_size_supported(bt, vlen);
   // Add rules here.
- 
+
   return ret_value;  // Per default match rules are supported.
 }