Provide fixes on top on LTTng 2.4

To make base address state tracing to work better or appliations that
fork without exec (e.g. daemons, web servers, ...) the following patch
is applied to lttng-ust:
lttng-ust/0001-Fix-Make-deadlocks-with-baddr-statedump-unlikely.patch

To work around an ARM specific compiler bug that causes babeltrace to
miscompile with optimizations the following patch is used:
babeltrace/do-not-optimize-parser.patch

To workaround a crosscompiling issue with babeltrace 1.2 the following
patch is used:
babeltrace/lttng-live-missing-header.patch

To enable building of lttng-modules for ARM the following modifications
are required to the recipe in poky:
packagegroup-core-tools-profile.bbappend
lttng-modules_2.4.0.bbappend

To enable compiling liburcu without --disable-compiler-tls on ARM the
following recipe is added:
liburcu_0.8.4.bb