simplify and beautify portBYTE_ALIGNMENT (#309)
diff --git a/include/portable.h b/include/portable.h
index 3768e2c..774d3b5 100644
--- a/include/portable.h
+++ b/include/portable.h
@@ -53,29 +53,17 @@
#if portBYTE_ALIGNMENT == 32
#define portBYTE_ALIGNMENT_MASK ( 0x001f )
-#endif
-
-#if portBYTE_ALIGNMENT == 16
+#elif portBYTE_ALIGNMENT == 16
#define portBYTE_ALIGNMENT_MASK ( 0x000f )
-#endif
-
-#if portBYTE_ALIGNMENT == 8
+#elif portBYTE_ALIGNMENT == 8
#define portBYTE_ALIGNMENT_MASK ( 0x0007 )
-#endif
-
-#if portBYTE_ALIGNMENT == 4
+#elif portBYTE_ALIGNMENT == 4
#define portBYTE_ALIGNMENT_MASK ( 0x0003 )
-#endif
-
-#if portBYTE_ALIGNMENT == 2
+#elif portBYTE_ALIGNMENT == 2
#define portBYTE_ALIGNMENT_MASK ( 0x0001 )
-#endif
-
-#if portBYTE_ALIGNMENT == 1
+#elif portBYTE_ALIGNMENT == 1
#define portBYTE_ALIGNMENT_MASK ( 0x0000 )
-#endif
-
-#ifndef portBYTE_ALIGNMENT_MASK
+#else
#error "Invalid portBYTE_ALIGNMENT definition"
#endif