winejoystick.drv: Use CP_UNIXCP instead of CP_ACP when converting a string that comes from the OS.

dlls/winejoystick.drv/joystick.c

diff --git a/dlls/winejoystick.drv/joystick.c b/dlls/winejoystick.drv/joystick.c
index 2967a50..9a6902e 100644
--- a/dlls/winejoystick.drv/joystick.c
+++ b/dlls/winejoystick.drv/joystick.c
@@ -221,7 +221,7 @@
 	  driverVersion, identString, nrOfAxes, nrOfButtons);
     lpCaps->wMid = MM_MICROSOFT;
     lpCaps->wPid = MM_PC_JOYSTICK;
-    MultiByteToWideChar(CP_ACP, 0, identString, -1, lpCaps->szPname, MAXPNAMELEN);
+    MultiByteToWideChar(CP_UNIXCP, 0, identString, -1, lpCaps->szPname, MAXPNAMELEN);
     lpCaps->szPname[MAXPNAMELEN-1] = '\0';
     lpCaps->wXmin = 0;
     lpCaps->wXmax = 0xFFFF;