mdadm: update to version 3.4

mdadm: update to version 3.4

3.3.4 -> 3.4

a) Removed the following upstreamed patch:
        1. 0001-Define-_POSIX_C_SOURCE-if-undefined.patch

b) Added following patches to fix uclibc,musl and x32 build failures
        1. 0001-mdadm.h-bswap-is-already-defined-in-uclibc.patch
        2. 0001-util.c-include-poll.h-instead-of-sys-poll.h.patch
        3. 0001-Fix-some-type-comparison-problems.patch
        4. 0001-Fix-the-path-of-corosync-and-dlm-header-files-check.patch

Signed-off-by: Maxin B. John <maxin.john@intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>