task-core-boot: Make sure the 'kernel' package is installed

The modules depend on kernel-base (renamed kernel-3.2.35) package,
the tasks depend on some modules and nothing needed the kernel package.

In OE Core/Poky the machines depend on kernel-modules which will pull
the kernel package into the rootfs. We do it by hand using the essential
depends and bumping the PR for the task-core-boot.

I have verified that on a kernel ugrade task-core-boot will be updated
and the kernel package is installed.

conf/machine/include/sysmobts.inc

@@ -20,6 +20,7 @@ MACHINE_FEATURES = "kernel26 serial"
 MACHINE_ESSENTIAL_EXTRA_RDEPENDS = "\
 	busybox-ifplugd \
 	watchdog \
+	kernel \
 	kernel-module-davinci-wdt \
 	kernel-module-dspdl \
 	kernel-module-dspdl-dm644x \

recipes-apps/tasks/task-core-boot.bbappend

@@ -1,3 +1,3 @@
-PRINC = "6"
+PRINC = "7"
 
 RDEPENDS_task-core-boot += ""