libyang CHANGE rename ambiguous lyp_ prefixed functions and structures

The 'p' in the lyp_ prefix is not unique since it may refer to printer
as well as parser. Some of the objects are connected with libyang output
object, so they are now prefixed by 'ly_out_' prefix. The rest
(lyp_print() or lyp_write()) is so generic that only the `ly_` prefix
can be used for them.
diff --git a/tests/utests/data/test_validation.c b/tests/utests/data/test_validation.c
index 16d742a..fde40de 100644
--- a/tests/utests/data/test_validation.c
+++ b/tests/utests/data/test_validation.c
@@ -1019,8 +1019,8 @@
     struct lyd_node *tree, *node;
     const struct lys_module *mod = ly_ctx_get_module_latest(ctx, "f");
 
-    struct lyp_out *out;
-    assert_non_null(out = lyp_new_memory(&str, 0));
+    struct ly_out *out;
+    assert_non_null(out = ly_out_new_memory(&str, 0));
 
     /* get defaults */
     tree = NULL;
@@ -1044,7 +1044,7 @@
             "<ll2 xmlns:ncwd=\"urn:ietf:params:xml:ns:yang:ietf-netconf-with-defaults\" ncwd:default=\"true\">dflt1</ll2>"
             "<ll2 xmlns:ncwd=\"urn:ietf:params:xml:ns:yang:ietf-netconf-with-defaults\" ncwd:default=\"true\">dflt2</ll2>"
         "</cont>");
-    lyp_out_reset(out);
+    ly_out_reset(out);
 
     /* create another explicit case and validate */
     node = lyd_new_term(NULL, mod, "l", "value");
@@ -1067,7 +1067,7 @@
             "<ll2 xmlns:ncwd=\"urn:ietf:params:xml:ns:yang:ietf-netconf-with-defaults\" ncwd:default=\"true\">dflt2</ll2>"
         "</cont>"
         "<l xmlns=\"urn:tests:f\">value</l>");
-    lyp_out_reset(out);
+    ly_out_reset(out);
 
     /* create explicit leaf-list and leaf and validate */
     node = lyd_new_term(NULL, mod, "d", "15");
@@ -1092,7 +1092,7 @@
         "<l xmlns=\"urn:tests:f\">value</l>"
         "<d xmlns=\"urn:tests:f\">15</d>"
         "<ll2 xmlns=\"urn:tests:f\">dflt2</ll2>");
-    lyp_out_reset(out);
+    ly_out_reset(out);
 
     /* create first explicit container, which should become implicit */
     node = lyd_new_inner(NULL, mod, "cont");
@@ -1115,7 +1115,7 @@
         "<l xmlns=\"urn:tests:f\">value</l>"
         "<d xmlns=\"urn:tests:f\">15</d>"
         "<ll2 xmlns=\"urn:tests:f\">dflt2</ll2>");
-    lyp_out_reset(out);
+    ly_out_reset(out);
 
     /* create second explicit container, which should become implicit, so the first tree node should be removed */
     node = lyd_new_inner(NULL, mod, "cont");
@@ -1137,7 +1137,7 @@
         "<l xmlns=\"urn:tests:f\">value</l>"
         "<d xmlns=\"urn:tests:f\">15</d>"
         "<ll2 xmlns=\"urn:tests:f\">dflt2</ll2>");
-    lyp_out_reset(out);
+    ly_out_reset(out);
 
     /* similar changes for nested defaults */
     assert_non_null(lyd_new_term(tree, NULL, "ll1", "def3"));
@@ -1156,10 +1156,10 @@
         "<l xmlns=\"urn:tests:f\">value</l>"
         "<d xmlns=\"urn:tests:f\">15</d>"
         "<ll2 xmlns=\"urn:tests:f\">dflt2</ll2>");
-    lyp_out_reset(out);
+    ly_out_reset(out);
 
     lyd_free_siblings(tree);
-    lyp_free(out, NULL, 1);
+    ly_out_free(out, NULL, 1);
 
     *state = NULL;
 }