Add ChangeLog entry for #15926

Signed-off-by: William Desportes <williamdes@wdes.fr>

ChangeLog

@@ -34,6 +34,7 @@ phpMyAdmin - ChangeLog
 - issue #15854 Fixed black borders for full screen mode on Designer
 - issue #15899 Fix "Uncaught TypeError: mb_strtoupper()" on the relational view of a view
 - issue        Fixed some php uncaught errors and notices on user missing extension
+- issue #15926 Fixed PhpMyAdmin\Core::getRealSize('8000M') returns a float instead of an int
 
 5.0.1 (2020-01-07)
 - issue #15719 Fixed error 500 when browsing a table when $cfg['LimitChars'] used a string and not an int value