Division between integers will also be integer.
Thus, to preserve fractional part explicitly
convert first operand to double.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 28d54aab05 ("examples: Introduce domtop")
Signed-off-by: Egor Makrushin <emakrushin@astralinux.ru>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>