LU-12634 osd-ldiskfs: bi_phys_segments removed from struct bio

LU-12634 osd-ldiskfs: bi_phys_segments removed from struct bio

Linux 5.3 removed the bi_phys_segments field in struct bio
Use bio_segments() if bi_phys_segments is not available

kernel-commit: 14ccb66b3f585b2bc21e7256c96090abed5a512c

Test-Parameters: trivial
Cray-bug-id: LUS-7689
Signed-off-by: Shaun Tancheff <stancheff@cray.com>
Change-Id: I87f2b1dc34f47a4eaa5ab5d6e55a903afc317011
Reviewed-on: https://review.whamcloud.com/35746
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Petros Koutoupis <pkoutoupis@cray.com>
Reviewed-by: Alex Zhuravlev <bzzz@whamcloud.com>
Reviewed-by: Patrick Farrell <pfarrell@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Oleg Drokin <green@whamcloud.com>