InnoDB: Remove unused get_wkb_of_default_point()

The function get_wkb_of_default_point() should never have been
added, and the cleanup in commit 56ff6f1b
should have removed it.

The unnecessary code was added in
mysql/mysql-server@0a27b72171c4449f506ad4e93df8c29fead1ed72
and mostly disabled in
mysql/mysql-server@8f11af7734509821b654f2c330dff5374c89073c.

In MariaDB, the types DATA_POINT and DATA_VAR_POINT are never used.
Instead, DATA_GEOMETRY continues to be used since 10.2.2, introduced by
mysql/mysql-server@673bad7c7e17701b69e29d0fbc4e2d68c1a7b613
in MySQL 5.7.1.

storage/innobase/gis/gis0geo.cc

@@ -801,35 +801,3 @@ rtree_area_overlapping(
 
 	return(area);
 }
-
-/** Get the wkb of default POINT value, which represents POINT(0 0)
-if it's of dimension 2, etc.
-@param[in]	n_dims		dimensions
-@param[out]	wkb		wkb buffer for default POINT
-@param[in]	len		length of wkb buffer
-@return non-0 indicate the length of wkb of the default POINT,
-0 if the buffer is too small */
-uint
-get_wkb_of_default_point(
-	uint	n_dims,
-	uchar*	wkb,
-	uint	len)
-{
-  // JAN: TODO: MYSQL 5.7 GIS
-  #define GEOM_HEADER_SIZE 16
-	if (len < GEOM_HEADER_SIZE + sizeof(double) * n_dims) {
-		return(0);
-	}
-
-	/** POINT wkb comprises SRID, wkb header(byte order and type)
-	and coordinates of the POINT */
-	len = GEOM_HEADER_SIZE + sizeof(double) * n_dims;
-	/** We always use 0 as default coordinate */
-	memset(wkb, 0, len);
-	/** We don't need to write SRID, write 0x01 for Byte Order */
-	mach_write_to_n_little_endian(wkb + SRID_SIZE, 1, 0x01);
-	/** Write wkbType::wkbPoint for the POINT type */
-	mach_write_to_n_little_endian(wkb + SRID_SIZE + 1, 4, wkbPoint);
-
-	return(len);
-}

storage/innobase/include/gis0geo.h

@@ -54,19 +54,6 @@ enum wkbByteOrder
   wkbNDR = 1     /* Little Endian */
 };
 
-/** Get the wkb of default POINT value, which represents POINT(0 0)
-if it's of dimension 2, etc.
-@param[in]	n_dims		dimensions
-@param[out]	wkb		wkb buffer for default POINT
-@param[in]	len		length of wkb buffer
-@return non-0 indicate the length of wkb of the default POINT,
-0 if the buffer is too small */
-uint
-get_wkb_of_default_point(
-	uint	n_dims,
-	uchar*	wkb,
-	uint	len);
-
 /*************************************************************//**
 Calculate minimal bounding rectangle (mbr) of the spatial object
 stored in "well-known binary representation" (wkb) format.