Fix type alignment handling for enums

The type alignment handling code used to determine the alignment size
for a given datatype was treating enums as if they were integers, but
that is incorrect.  It should (just like integers and pointers) have
its alignment set to match its size, but it should avoid the explicit
void-checking that is done for integers.

Without this patch, libdtrace linked with newer versions of libctf
will see a test failure in unittest/sizeof/tst.SizeofDataTypes.d for
datatype 'new_enum'.

Signed-off-by: Kris Van Hees <kris.van.hees@oracle.com>

libdtrace/dt_parser.c

@@ -1630,7 +1630,6 @@ dt_node_decl(void)
 			size = ctf_type_size(dtt.dtt_ctfp, dtt.dtt_type);
 
 			switch (kind) {
-			case CTF_K_ENUM:
 			case CTF_K_INTEGER:
 				if (ctf_type_encoding(dtt.dtt_ctfp, type,
 						      &cte) == 0 &&
@@ -1639,6 +1638,7 @@ dt_node_decl(void)
 						"cannot have void object: %s\n",
 						dsp->ds_ident);
 				/*FALLTHRU*/
+			case CTF_K_ENUM:
 			case CTF_K_POINTER:
 				alignment = size;
 				break;