Description:

```--------
After compiling from source, during make test I got the following error:

test main.loaddata failed with error
CURRENT_TEST: main.loaddata
mysqltest: At line 592: query 'LOAD DATA INFILE 'tmpp.txt' INTO TABLE t1
CHARACTER SET ucs2
(@b) SET a=REVERSE(@b)' failed: 1115: Unknown character set: 'ucs2'

I noticed other tests are skipped because of no ucs2
main.mix2_myisam_ucs2                    [ skipped ]  Test requires:'
have_ucs2'

Should main.loaddata be skipped if there is no ucs2

How To Repeat:
```

----------
Run make test on compiled source that doesn't have ucs2

Suggested fix:
-------------
the failing piece of the test should be moved from mysql-test/t/loaddata.test to
mysql-test/t/ctype_ucs.test.

mysql-test/r/loaddata.result

@@ -504,37 +504,6 @@ CREATE TABLE t1 (id INT NOT NULL);
 LOAD DATA LOCAL INFILE 'tb.txt' INTO TABLE t1;
 DROP TABLE t1;
 #
-# Bug #51876 : crash/memory underrun when loading data with ucs2 
-#   and reverse() function
-#
-# Problem # 1 (original report): wrong parsing of ucs2 data
-SELECT '00' UNION SELECT '10' INTO OUTFILE 'tmpp.txt';
-CREATE TABLE t1(a INT);
-LOAD DATA INFILE 'tmpp.txt' INTO TABLE t1 CHARACTER SET ucs2
-(@b) SET a=REVERSE(@b);
-Warnings:
-Warning	1366	Incorrect integer value: '?' for column 'a' at row 1
-Warning	1366	Incorrect integer value: '?' for column 'a' at row 2
-# should return 2 zeroes (as the value is truncated)
-SELECT * FROM t1;
-a
-0
-0
-DROP TABLE t1;
-# Problem # 2 : if you write and read ucs2 data to a file they're lost
-SELECT '00' UNION SELECT '10' INTO OUTFILE 'tmpp2.txt' CHARACTER SET ucs2;
-CREATE TABLE t1(a INT);
-LOAD DATA INFILE 'tmpp2.txt' INTO TABLE t1 CHARACTER SET ucs2
-(@b) SET a=REVERSE(@b);
-# should return 0 and 1 (10 reversed)
-SELECT * FROM t1;
-a
-0
-1
-DROP TABLE t1;
-#
-
-
 # Bug#11765139  58069: LOAD DATA INFILE: VALGRIND REPORTS INVALID MEMORY READS AND WRITES WITH U
 #
 CREATE TABLE t1(f1 INT);