kernel: drop 6.6 support

It could be argued that we could keep the fragments and virtualization
.inc file for old versions, as they won't trigger and immediate issue
for configurations that are using the older supported kernel versions.

BUT, we could extend that comment to any / all versions ever supported
by OEcore.

Since 6.6 isn't actively being tested in master, let's drop all
the references and only have 6.12 active. If someone does need the
older kernel support, then the support could be restored.

Signed-off-by: Bruce Ashfield <bruce.ashfield@gmail.com>

dynamic-layers/raspberrypi/recipes-kernel/linux/linux-yocto_6.6.bbappend

@@ -1,6 +0,0 @@
-# Enable use of the linux-yocto kernel for the Raspberry Pi 4
-KBRANCH:raspberrypi4-64 ?= "v6.6/standard/bcm-2xxx-rpi"
-KMACHINE:raspberrypi4-64 ?= "bcm-2xxx-rpi4"
-COMPATIBLE_MACHINE:raspberrypi4-64 = "(raspberrypi4-64)"
-
-require linux-yocto_xen-rpi.inc

recipes-kernel/linux/linux-yocto_6.6_virtualization.inc

@@ -1,4 +0,0 @@
-# include the baseline meta virtualization configuration options
-# after this include, we can do version specific things
-
-include linux-yocto_virtualization.inc

recipes-kernel/linux/yocto-cfg-fragments-6.6.bb

@@ -1,37 +0,0 @@
-HOMEPAGE = "https://git.yoctoproject.org/cgit/cgit.cgi/yocto-kernel-cache/"
-SUMMARY = "Kernel configuration fragments"
-DESCRIPTION = "Typically used as part of a kernel clone, this is the standalone \
-fragment repository. Making it available to other fragment management schemes \
-"
-SECTION = "devel"
-
-LICENSE = "MIT"
-LIC_FILES_CHKSUM = "file://COPYING.MIT;md5=3da9cfbcb788c80a0384361b4de20420"
-
-do_configure[noexec] = "1"
-do_compile[noexec] = "1"
-INHIBIT_DEFAULT_DEPS = "1"
-
-LINUX_VERSION ?= "6.6"
-PV = "v${LINUX_VERSION}+git${SRCREV}"
-
-SRCREV = "4a494b202029e94a72ebb3c3966d9f1d249900f3"
-SRC_URI = "\
-        git://git.yoctoproject.org/yocto-kernel-cache;branch=yocto-${LINUX_VERSION} \
-        "
-
-S = "${WORKDIR}/git"
-
-do_install() {
-    install -d ${D}${base_prefix}/kcfg
-
-    # copy the configuration fragments over to the native deploy
-    cp -r ${S}/* ${D}${base_prefix}/kcfg
-    # scripts bring in a bash dependency we don't want
-    rm -rf ${D}${base_prefix}/kcfg/scripts
-}
-
-FILES:${PN} += "kcfg/"
-SYSROOT_DIRS += "${base_prefix}/kcfg"
-BBCLASSEXTEND = "native nativesdk"
-