src/meta-openembedded:libqb: upgrade 2.0.3 -> 2.0.4

The most important fix in this release is that we no longer log errors inside
the signal handler in loop_poll.c
This could cause an application hang in some circumstances.

Changelog is as follows:
doxygen2man: print structure descriptions
(ClusterLabs/libqb#443)

Fix pthread returns
(ClusterLabs/libqb#444)

poll: Don't log in a signal handler
(ClusterLabs/libqb#447)

Bump library version for v2.0.4

Implement heap based timer list
(ClusterLabs/libqb#439)

build: Fix undefined pthread reference.
(ClusterLabs/libqb#440)

Signed-off-by: Wang Mingyu <[email protected]>
Signed-off-by: Khem Raj <[email protected]>