V4L/DVB (13530): Fix wrong parameter order in memset

Edwin Török found the following:

In function ‘memset’,
inlined from ‘ir_input_init’ at drivers/media/common/ir-functions.c:67:
/home/edwin/builds/linux-2.6/arch/x86/include/asm/string_64.h:61:
warning: call to ‘__warn_memset_zero_len’ declared with attribute
warning: memset used with constant zero length parameter; this could be
due to transposed parameters
memset(ir->ir_codes, sizeof(ir->ir_codes), 0);

In actual practice the only caller I can find happens to already have cleared
the buffer before calling ir_input_init.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>