libyang REFACTOR rename LY_PREFIX_FORMAT values

Reflect that the value format is the primary concern of the enum, the prefix
interpretation is only based on the format.
diff --git a/tests/utests/schema/test_parser_yin.c b/tests/utests/schema/test_parser_yin.c
index c283570..d492591 100644
--- a/tests/utests/schema/test_parser_yin.c
+++ b/tests/utests/schema/test_parser_yin.c
@@ -22,6 +22,7 @@
 #include "in.h"
 #include "parser_internal.h"
 #include "schema_compile.h"
+#include "tree.h"
 #include "tree_edit.h"
 #include "tree_schema.h"
 #include "tree_schema_internal.h"
@@ -122,7 +123,7 @@
 #define ELEMENT_WRAPPER_END "</status>"
 
 #define TEST_1_CHECK_LYSP_EXT_INSTANCE(NODE, INSUBSTMT)\
-    CHECK_LYSP_EXT_INSTANCE((NODE), NULL, 1, INSUBSTMT, 0, "myext:c-define", LY_PREF_XML)
+    CHECK_LYSP_EXT_INSTANCE((NODE), NULL, 1, INSUBSTMT, 0, "myext:c-define", LY_VALUE_XML)
 
 struct lys_yin_parser_ctx *YCTX;
 
@@ -336,7 +337,7 @@
 
     ret = yin_parse_extension_instance(YCTX, LY_STMT_CONTACT, 0, &exts);
     assert_int_equal(ret, LY_SUCCESS);
-    CHECK_LYSP_EXT_INSTANCE(exts, NULL, 1, LY_STMT_CONTACT, 0, "myext:ext", LY_PREF_XML);
+    CHECK_LYSP_EXT_INSTANCE(exts, NULL, 1, LY_STMT_CONTACT, 0, "myext:ext", LY_VALUE_XML);
 
     CHECK_LYSP_STMT(exts->child, arg, 0, LYS_YIN_ATTR, 0, 1, stmt);
     stmt = "value";
@@ -356,7 +357,7 @@
 
     ret = yin_parse_extension_instance(YCTX, LY_STMT_CONTACT, 0, &exts);
     assert_int_equal(ret, LY_SUCCESS);
-    CHECK_LYSP_EXT_INSTANCE(exts, NULL, 0, LY_STMT_CONTACT, 0, "myext:extension-elem", LY_PREF_XML);
+    CHECK_LYSP_EXT_INSTANCE(exts, NULL, 0, LY_STMT_CONTACT, 0, "myext:extension-elem", LY_VALUE_XML);
     lysp_ext_instance_free(UTEST_LYCTX, exts);
     LY_ARRAY_FREE(exts);
     exts = NULL;
@@ -378,7 +379,7 @@
     ret = yin_parse_extension_instance(YCTX, LY_STMT_CONTACT, 0, &exts);
     assert_int_equal(ret, LY_SUCCESS);
 
-    CHECK_LYSP_EXT_INSTANCE(exts, NULL, 1, LY_STMT_CONTACT, 0, "myext:ext", LY_PREF_XML);
+    CHECK_LYSP_EXT_INSTANCE(exts, NULL, 1, LY_STMT_CONTACT, 0, "myext:ext", LY_VALUE_XML);
 
     stmt = "attr1";
     arg = "text1";
@@ -545,7 +546,7 @@
     const char *exts_name = "myext:custom";
     const char *exts_arg = "totally amazing extension";
 
-    CHECK_LYSP_EXT_INSTANCE(exts, exts_arg, 0, LY_STMT_PREFIX, 0, exts_name, LY_PREF_XML);
+    CHECK_LYSP_EXT_INSTANCE(exts, exts_arg, 0, LY_STMT_PREFIX, 0, exts_name, LY_VALUE_XML);
     assert_string_equal(value, "wsefsdf");
     assert_string_equal(units, "radians");
     assert_string_equal(when_p->cond, "condition...");