Padding and reserved fields are declared such that they must be
zeroed, so verify that they're all zero in the respective ioctl
functions.

Derived from original patch by mlankhorst.

v2:
	Removed extensions checks where there were none originally. (José)
	Moved extraneous parentheses to the correct places. (Lucas)
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Christopher Snowhill <kode54@gmail.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>