vfio: platform: mark symbols static where possible

We get a few warnings when building kernel with W=1:
drivers/vfio/platform/vfio_platform_common.c:76:5: warning: no previous prototype for 'vfio_platform_acpi_call_reset' [-Wmissing-prototypes]
drivers/vfio/platform/vfio_platform_common.c:98:6: warning: no previous prototype for 'vfio_platform_acpi_has_reset' [-Wmissing-prototypes]
drivers/vfio/platform/vfio_platform_common.c:640:5: warning: no previous prototype for 'vfio_platform_of_probe' [-Wmissing-prototypes]
drivers/vfio/platform/reset/vfio_platform_amdxgbe.c:59:5: warning: no previous prototype for 'vfio_platform_amdxgbe_reset' [-Wmissing-prototypes]
drivers/vfio/platform/reset/vfio_platform_calxedaxgmac.c:60:5: warning: no previous prototype for 'vfio_platform_calxedaxgmac_reset' [-Wmissing-prototypes]
....

In fact, these functions are only used in the file in which they are
declared and don't need a declaration, but can be made static.
so this patch marks these functions with 'static'.

Signed-off-by: Baoyou Xie <[e-mail]>
Acked-by: Arnd Bergmann <[e-mail]>
Reviewed-by: Eric Auger <[e-mail]>
Reviewed-by: Baptiste Reynal <[e-mail]>
Signed-off-by: Alex Williamson <[e-mail]>

drivers/vfio/platform/reset/vfio_platform_amdxgbe.c

···
 	iowrite32(value, ioaddr + ((mmd_address & 0xff) << 2));
 }
 
-int vfio_platform_amdxgbe_reset(struct vfio_platform_device *vdev)
+static int vfio_platform_amdxgbe_reset(struct vfio_platform_device *vdev)
 {
 	struct vfio_platform_region *xgmac_regs = &vdev->regions[0];
 	struct vfio_platform_region *xpcs_regs = &vdev->regions[1];

drivers/vfio/platform/reset/vfio_platform_calxedaxgmac.c

···
 	writel(value, ioaddr + XGMAC_CONTROL);
 }
 
-int vfio_platform_calxedaxgmac_reset(struct vfio_platform_device *vdev)
+static int vfio_platform_calxedaxgmac_reset(struct vfio_platform_device *vdev)
 {
 	struct vfio_platform_region *reg = &vdev->regions[0];
 

drivers/vfio/platform/vfio_platform_common.c

···
 	return WARN_ON(!vdev->acpihid) ? -EINVAL : 0;
 }
 
-int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev,
+static int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev,
 				  const char **extra_dbg)
 {
 #ifdef CONFIG_ACPI
···
 #endif
 }
 
-bool vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev)
+static bool vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev)
 {
 #ifdef CONFIG_ACPI
 	struct device *dev = vdev->device;
···
 	.mmap		= vfio_platform_mmap,
 };
 
-int vfio_platform_of_probe(struct vfio_platform_device *vdev,
+static int vfio_platform_of_probe(struct vfio_platform_device *vdev,
 			   struct device *dev)
 {
 	int ret;