[KERNEL][CLASS] Fix reduntant inheritance.

The classes kernel-yocto and kernel are already inherited in
kernel-seco so they are redundant.

Signed-off-by: Nicola Sparnacci <nicola.sparnacci@seco.com>

recipes-kernel/linux/linux-seco.inc

@@ -7,7 +7,7 @@ SECO Boards. It includes support for many IPs such as GPU, VPU and IPU."
 
 LIC_FILES_CHKSUM = "file://COPYING;md5=6bc538ed5bd9a7fc9398086aedcd7e46"
 
-inherit kernel-yocto kernel pkgconfig kernel-seco
+inherit pkgconfig kernel-seco
 
 DEPENDS += "lzop-native bc-native"