Post push test fix for show_check.test.

Fix for bug#45740 introduced test case using SHOW TABLE STATUS against a Memory table using latin1 character in table name.
The test failed on Windows and FreeBSD due to a difference in the value for Avg_row_length.
The average row length normally depends on the values for data length and row count. According to the 5.5 manual data length is approximate with Memory tables.
With MyISAM and InnoDB the Avg_row_length is the same on Windows and Solaris.
The solution implemented by this patch is to mask out the value for Avg_row_length, as it may vary when using Memory tables.

mysql-test/r/show_check.result

@@ -1334,7 +1334,7 @@ CREATE DATABASE `
 CREATE TABLE ``.`` (a int) ENGINE=Memory;
 SHOW TABLE STATUS FROM `` LIKE '';
 Name	Engine	Version	Row_format	Rows	Avg_row_length	Data_length	Max_data_length	Index_length	Data_free	Auto_increment	Create_time	Update_time	Check_time	Collation	Checksum	Create_options	Comment
-	MEMORY	10	Fixed	0	8	#	#	#	0	NULL	NULL	NULL	NULL	latin1_swedish_ci	NULL		
+	MEMORY	10	Fixed	0	#	#	#	#	0	NULL	NULL	NULL	NULL	latin1_swedish_ci	NULL		
 DROP DATABASE ``;
 show columns from `#mysql50#????????`;
 Got one of the listed errors

mysql-test/t/show_check.test

@@ -1073,7 +1073,7 @@ set names latin1;
 SET NAMES latin1;
 CREATE DATABASE ``;
 CREATE TABLE ``.`` (a int) ENGINE=Memory;
---replace_column 7 # 8 # 9 #
+--replace_column 6 # 7 # 8 # 9 #
 SHOW TABLE STATUS FROM `` LIKE '';
 DROP DATABASE ``;