powerpc/pseries: Cleanup on pseries_eeh_get_state()

This cleans up pseries_eeh_get_state(), no functional changes:

   * Return EEH_STATE_NOT_SUPPORT early when the 2nd RTAS output
     argument is zero to avoid nested if statements.
   * Skip clearing bits in the PE state represented by variable
     "result" to simplify the code.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/platforms/pseries/eeh_pseries.c

@@ -433,29 +433,24 @@ static int pseries_eeh_get_state(struct eeh_pe *pe, int *state)
 		return ret;
 
 	/* Parse the result out */
-	result = 0;
-	if (rets[1]) {
+	if (!rets[1])
+		return EEH_STATE_NOT_SUPPORT;
+
 	switch(rets[0]) {
 	case 0:
-			result &= ~EEH_STATE_RESET_ACTIVE;
-			result |= EEH_STATE_MMIO_ACTIVE;
-			result |= EEH_STATE_DMA_ACTIVE;
+		result = EEH_STATE_MMIO_ACTIVE |
+			 EEH_STATE_DMA_ACTIVE;
 		break;
 	case 1:
-			result |= EEH_STATE_RESET_ACTIVE;
-			result |= EEH_STATE_MMIO_ACTIVE;
-			result |= EEH_STATE_DMA_ACTIVE;
+		result = EEH_STATE_RESET_ACTIVE |
+			 EEH_STATE_MMIO_ACTIVE  |
+			 EEH_STATE_DMA_ACTIVE;
 		break;
 	case 2:
-			result &= ~EEH_STATE_RESET_ACTIVE;
-			result &= ~EEH_STATE_MMIO_ACTIVE;
-			result &= ~EEH_STATE_DMA_ACTIVE;
+		result = 0;
 		break;
 	case 4:
-			result &= ~EEH_STATE_RESET_ACTIVE;
-			result &= ~EEH_STATE_MMIO_ACTIVE;
-			result &= ~EEH_STATE_DMA_ACTIVE;
-			result |= EEH_STATE_MMIO_ENABLED;
+		result = EEH_STATE_MMIO_ENABLED;
 		break;
 	case 5:
 		if (rets[2]) {
@@ -468,9 +463,6 @@ static int pseries_eeh_get_state(struct eeh_pe *pe, int *state)
 	default:
 		result = EEH_STATE_NOT_SUPPORT;
 	}
-	} else {
-		result = EEH_STATE_NOT_SUPPORT;
-	}
 
 	return result;
 }