Fix PSPSaveDialog::Update

Fix Miyako lock up in saving screen

My changed PPSSPP log
https://gist.github.com/sum2012/03ba496b0760a160e63b

JPCSP trace log
https://gist.github.com/sum2012/4ac98b8de6d69fca6b22

Match JPCSP trace log except
HLE\sceUtility.cpp:152 00000004=sceUtilitySavedataGetStatus()