kernel/linux: Cleanup unneeded files from 'headers_check' and 'headers_install'

headers_install makes .install and ..install.cmd files.
headers_check makes .check and ..check.cmd files.
Remove these files uncoditionaly after installing (and checking) header files
into the sys-root.

Signed-off-by: Bryan Hundven <bryanhundven@gmail.com>
[Yann E. MORIN: reformat the patch, move hunk out of headers_check conditional]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

 # This file declares functions for bare metal kernel (IE. none)

 # Copyright 2008 Yann E. MORIN

 # Licensed under the GPL v2. See COPYING in the root of this package

 CT_DoKernelTupleValues() {

     # For bare-metal, there is no kernel part in the tuple

     CT_TARGET_KERNEL=

 }

 do_kernel_get() {

     :

 }

 do_kernel_extract() {

     :

 }

 do_kernel_headers() {

     :

 }