dmaengine: pl330: make unexported functions static

Whilst running sparse on pl330 driver it was noticed there are
two functions that are not static but not exported to any other
users in the kernel.

Fix the following warnings by making 'pl330_pause' and the
'pl330_get_current_xferred_count' static:

pl330.c:2165:5: warning: symbol 'pl330_pause' was not declared. Should it be static?
pl330.c:2206:5: warning: symbol 'pl330_get_current_xferred_count' was not declared. Should it be static?

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
--
Vinod Koul <vinod.koul@intel.com>
Dan Williams <dan.j.williams@intel.com>
DMA List <dmaengine@vger.kernel.org>
Maxime Ripard <maxime.ripard@free-electrons.com>
Jassi Brar <jassisinghbrar@gmail.com>
Liviu Dudau <Liviu.Dudau@arm.com>
Linux ARM Kernel <linux-arm-kernel@lists.infradead.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>