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/src/printer_data.h b/src/printer_data.h
index 921793f..d9065bb 100644
--- a/src/printer_data.h
+++ b/src/printer_data.h
@@ -37,12 +37,12 @@
                                       Note that this is the default value when no WD option is specified. */
 #define LYDP_WD_TRIM       0x10  /**< Do not print the nodes with the value equal to their default value */
 #define LYDP_WD_ALL        0x20  /**< Include implicit default nodes */
-#define LYDP_WD_ALL_TAG    0x40  /**< Same as #LYP_WD_ALL but also adds attribute 'default' with value 'true' to
+#define LYDP_WD_ALL_TAG    0x40  /**< Same as #LYDP_WD_ALL but also adds attribute 'default' with value 'true' to
                                       all nodes that has its default value. The 'default' attribute has namespace:
                                       urn:ietf:params:xml:ns:netconf:default:1.0 and thus the attributes are
                                       printed only when the ietf-netconf-with-defaults module is present in libyang
                                       context (but in that case this namespace is always printed). */
-#define LYDP_WD_IMPL_TAG   0x80  /**< Same as LYP_WD_ALL_TAG but the attributes are added only to the nodes that
+#define LYDP_WD_IMPL_TAG   0x80  /**< Same as LYDP_WD_ALL_TAG but the attributes are added only to the nodes that
                                       are not explicitly present in the original data tree despite their
                                       value is equal to their default value.  There is the same limitation regarding
                                       the presence of ietf-netconf-with-defaults module in libyang context. */
@@ -53,13 +53,13 @@
 /**
  * @brief Common YANG data printer.
  *
- * @param[in] out Printer handler for a specific output. Use lyp_*() functions to create the handler and lyp_free() to remove the handler.
+ * @param[in] out Printer handler for a specific output. Use ly_out_*() functions to create and free the handler.
  * @param[in] root The root element of the (sub)tree to print.
  * @param[in] format Output format.
- * @param[in] options [Data printer flags](@ref dataprinterflags). With \p format LYD_LYB, only #LYP_WITHSIBLINGS option is accepted.
+ * @param[in] options [Data printer flags](@ref dataprinterflags). With \p format LYD_LYB, only #LYDP_WITHSIBLINGS option is accepted.
  * @return Number of printed characters (excluding the null byte used to end the string) in case of success.
  * @return Negative value failure (absolute value corresponds to LY_ERR values).
  */
-ssize_t lyd_print(struct lyp_out *out, const struct lyd_node *root, LYD_FORMAT format, int options);
+ssize_t lyd_print(struct ly_out *out, const struct lyd_node *root, LYD_FORMAT format, int options);
 
 #endif /* LY_PRINTER_DATA_H_ */