kgdb,x86: remove redundant test

The for loop starts with a breakno of 0, and ends when it's 4. so
this test is always true.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>