kernel/sysctl.c: remove duplicate UINT_MAX check on do_proc_douintvec_conv()

kernel/sysctl.c: remove duplicate UINT_MAX check on do_proc_douintvec_conv()

do_proc_douintvec_conv() has two UINT_MAX checks, we can remove one.
This has no functional changes other than fixing a compiler warning:

  kernel/sysctl.c:2190]: (warning) Identical condition '*lvalp>UINT_MAX', second condition is always false

Fixes: 74bd190fe0943 ("sysctl: simplify unsigned int support")
Link: http://lkml.kernel.org/r/20170919072918.12066-1-mcgrof@kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Reported-by: David Binderman <dcb314@hotmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>