tools/lib/traceevent/parse-filter.c: clean up clang build warning

The uniform structure filter_arg sets its union based on the difference
of enum filter_arg_type, However, some functions use implicit type
conversion obviously.

warning: implicit conversion from enumeration type 'enum filter_exp_type'
	 to different enumeration type 'enum filter_op_type'

warning: implicit conversion from enumeration type 'enum filter_cmp_type'
	 to different enumeration type 'enum filter_exp_type'

Link: http://lkml.kernel.org/r/1509938415-113825-1-git-send-email-cj.chengjian@huawei.comSigned-off-by: Cheng Jian <cj.chengjian@huawei.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Xie XiuQi <xiexiuqi@huawei.com>
Cc: Li Bin <huawei.libin@huawei.com>
Cc: Steven Rostedt (Red Hat) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

tools/lib/traceevent/parse-filter.c

@@ -436,13 +436,13 @@ create_arg_exp(enum filter_exp_type etype)
 		return NULL;
 
 	arg->type = FILTER_ARG_EXP;
-	arg->op.type = etype;
+	arg->exp.type = etype;
 
 	return arg;
 }
 
 static struct filter_arg *
-create_arg_cmp(enum filter_exp_type etype)
+create_arg_cmp(enum filter_cmp_type ctype)
 {
 	struct filter_arg *arg;
 
@@ -452,7 +452,7 @@ create_arg_cmp(enum filter_exp_type etype)
 
 	/* Use NUM and change if necessary */
 	arg->type = FILTER_ARG_NUM;
-	arg->op.type = etype;
+	arg->num.type = ctype;
 
 	return arg;
 }