linux: Disable CAPI support

Support for the CAPI (CXL) driver in Skiroot is unnecessary and
potentially harmful as CAPI does not support being used over a kexec,
which could result in CAPI devices being unavailable in the host.

Signed-off-by: Samuel Mendoza-Jonas <sam@mendozajonas.com>
diff --git a/openpower/configs/linux/skiroot_defconfig b/openpower/configs/linux/skiroot_defconfig
index 20d4358..63e08de 100644
--- a/openpower/configs/linux/skiroot_defconfig
+++ b/openpower/configs/linux/skiroot_defconfig
@@ -232,3 +232,4 @@
 # CONFIG_CRYPTO_HW is not set
 CONFIG_CMDLINE_BOOL=y
 CONFIG_CMDLINE="console=tty0 console=hvc0"
+CONFIG_CXL=n