Add "conditional=true" annotation for setPackagesSuspended API.

We have the @RequiresPermission(Manifest.permission.SUSPEND_APPS)
annotation for PackageManager.setPackagesSuspended API, but we
allow the device owner and profile owner to use this API directly
without the permission "Manifest.permission.SUSPEND_APPS" in the
service implementation. So we need to add "conditional=true" to
@RequiresPermission annotation for this API.

Bug: 284455031
Test: build pass and boot success
Change-Id: I9f31f074736afd216935f4112584fef9ea98e2bf