Fix wide char format specifier in libio/tst-bz24153.c.

On big endian systems the test fails with:
tst-bz24153.c:88: numeric comparison failure
   left: 1660944385 (0x63000001); from: ch
  right: 99 (0x63); from: L'c'
tst-bz24153.c:90: numeric comparison failure
   left: 1677721601 (0x64000001); from: ch
  right: 100 (0x64); from: L'd'
error: 2 test failures

One 'char' ("%c") is stored to the 'wchar_t *':
ch = 0x00000001 | 0x63000000

This patch is using "%lc" as format specifier to read a wchar_t.

ChangeLog:

	* libio/tst-bz24153.c (wide): Use wide char format specifier.