get rid of DEBUG_WRITECOUNT

it only makes control flow in __fput() and friends more convoluted.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

arch/sh/configs/rsk7203_defconfig

@@ -128,7 +128,6 @@ CONFIG_DEBUG_MUTEXES=y
 CONFIG_DEBUG_SPINLOCK_SLEEP=y
 CONFIG_DEBUG_INFO=y
 CONFIG_DEBUG_VM=y
-CONFIG_DEBUG_WRITECOUNT=y
 CONFIG_DEBUG_LIST=y
 CONFIG_DEBUG_SG=y
 CONFIG_FRAME_POINTER=y