staging: vchiq_arm: change vchiq_platform_init from global to static

Smatch reports this issue
vchiq_arm.c:466:5: warning: symbol 'vchiq_platform_init'
  was not declared. Should it be static?

vchiq_platform_init is only used in vchiq_arm.c.  Single
file variables should not be global so change
vchiq_platform_init's storage-class specifier to static.

Signed-off-by: Tom Rix <trix@redhat.com>

drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c

@@ -463,7 +463,7 @@ free_pagelist(struct vchiq_pagelist_info *pagelistinfo,
 	cleanup_pagelistinfo(pagelistinfo);
 }
 
-int vchiq_platform_init(struct platform_device *pdev, struct vchiq_state *state)
+static int vchiq_platform_init(struct platform_device *pdev, struct vchiq_state *state)
 {
 	struct device *dev = &pdev->dev;
 	struct vchiq_drvdata *drvdata = platform_get_drvdata(pdev);