lib/math: add int_sqrt test suite

Adds test suite for integer based square root function.

The test suite is designed to verify the correctness of the int_sqrt()
math library function.

Link: https://lkml.kernel.org/r/20241213042701.1037467-1-luis.hernandez093@gmail.com


Signed-off-by: Luis Felipe Hernandez <luis.hernandez093@gmail.com>
Reviewed-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Cc: David Gow <davidgow@google.com>
Cc: Ricardo B. Marliere <rbm@suse.com>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>