sys-kernel/coreos-modules: remove CONFIG_DEBUG_CREDENTIALS

```
 make[1]: Leaving directory '/build/amd64-usr/var/tmp/portage/sys-kernel/coreos-modules-6.6.8/work/coreos-modules-6.6.8/build'
 make: Leaving directory '/build/amd64-usr/var/tmp/portage/sys-kernel/coreos-modules-6.6.8/work/coreos-modules-6.6.8/source'
  * ERROR: sys-kernel/coreos-modules-6.6.8::coreos failed (configure phase):
  *   Requested options not enabled in build:
  *     CONFIG_DEBUG_CREDENTIALS
  *
  * Call stack:
  *     ebuild.sh, line  136:  Called src_configure
  *   environment, line 2498:  Called coreos-kernel_src_configure
  *   environment, line  901:  Called die
  * The specific snippet of code:
  *           die "Requested options not enabled in build:
  * ${missing}";
```
Upstream commit: torvalds/linux@ae19141

Signed-off-by: Mathieu Tortuyaux <[email protected]>

Author: tormath1

sdk_container/src/third_party/coreos-overlay/sys-kernel/coreos-modules/files/commonconfig-6.6

@@ -139,7 +139,6 @@ CONFIG_CRYPTO_USER_API_HASH=m
 CONFIG_CRYPTO_USER_API_SKCIPHER=m
 CONFIG_CUSE=m
 CONFIG_DCB=y
-CONFIG_DEBUG_CREDENTIALS=y
 CONFIG_DEBUG_FS=y
 CONFIG_DEBUG_INFO_BTF=y
 CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y