[media] bdisp-debug: don't try to divide by s64

There are several warnings there, on some architectures, related
to dividing a s32 by a s64 value:

drivers/media/platform/sti/bdisp/bdisp-debug.c:594: warning: comparison of distinct pointer types lacks a cast
drivers/media/platform/sti/bdisp/bdisp-debug.c:594: warning: right shift count >= width of type
drivers/media/platform/sti/bdisp/bdisp-debug.c:594: warning: passing argument 1 of '__div64_32' from incompatible pointer type
drivers/media/platform/sti/bdisp/bdisp-debug.c:595: warning: comparison of distinct pointer types lacks a cast
drivers/media/platform/sti/bdisp/bdisp-debug.c:595: warning: right shift count >= width of type
drivers/media/platform/sti/bdisp/bdisp-debug.c:595: warning: passing argument 1 of '__div64_32' from incompatible pointer type  CC [M]  drivers/media/tuners/mt2060.o
drivers/media/platform/sti/bdisp/bdisp-debug.c:596: warning: comparison of distinct pointer types lacks a cast
drivers/media/platform/sti/bdisp/bdisp-debug.c:596: warning: right shift count >= width of type
drivers/media/platform/sti/bdisp/bdisp-debug.c:596: warning: passing argument 1 of '__div64_32' from incompatible pointer type
drivers/media/platform/sti/bdisp/bdisp-debug.c:597: warning: comparison of distinct pointer types lacks a cast
drivers/media/platform/sti/bdisp/bdisp-debug.c:597: warning: right shift count >= width of type
drivers/media/platform/sti/bdisp/bdisp-debug.c:597: warning: passing argument 1 of '__div64_32' from incompatible pointer type

That doesn't make much sense. What the driver is actually trying
to do is to divide one second by a value. So, check the range
before dividing. That warrants the right result and will remove
the warnings on non-64 bits archs.

Also fixes this warning:
drivers/media/platform/sti/bdisp/bdisp-debug.c:588: warning: comparison of distinct pointer types lacks a cast

by using div64_s64() instead of calling do_div() directly.

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>