mfd: don't export wm3850 static functions

October 10th linux-next build (powerpc allyesconfig) failed like this:

drivers/mfd/wm8350-core.c:1131: error: __ksymtab_wm8350_create_cache causes a section type conflict

Caused by commit 89b4012b ("mfd: Core
support for the WM8350 AudioPlus PMIC"). wm8350_create_cache is not used
elsewhere, so remove the EXPORT_SYMBOL.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@openedhand.com>

drivers/mfd/wm8350-core.c

@@ -1128,7 +1128,6 @@ static int wm8350_create_cache(struct wm8350 *wm8350, int mode)
 out:
 	return ret;
 }
-EXPORT_SYMBOL_GPL(wm8350_create_cache);
 
 /*
  * Register a client device.  This is non-fatal since there is no need to