linux: added support for fully preemptive kernel (-rt patches).

rules/linux/rt.bash

@@ -0,0 +1,27 @@
+. "$cfg_dir_rules/$pkg/default.bash"
+
+version=\
+(
+    '3.14.64-rt67'
+)
+
+url=\
+(
+    "https://www.kernel.org/pub/linux/kernel/v3.x/linux-$(linux_mmp_version).tar.xz"
+    "https://www.kernel.org/pub/linux/kernel/projects/rt/$(linux_mm_version)/patch-$version.patch.gz"
+)
+
+md5=\
+(
+    'd68173a31fb60e2195a4015fe1f83e97'
+    '03be9388659d844c362e507ddba2d777'
+)
+
+maintainer=\
+(
+    'Ricardo Martins <rasm@oceanscan-mst.com>'
+)
+
+patches=("$cfg_dir_downloads/patch-$version.patch.gz" "${patches[@]}")
+
+build_dir="linux-$(linux_mmp_version)"