libcurl: bump version to 7.49.0
Fixes CVE-2016-3739, https://curl.haxx.se/docs/adv_20160518.html.
Signed-off-by: Vicente Olivert Riera <Vincent.Riera@imgtec.com>
[Thomas: add reference to the CVE being fixed, pointed by Gustavo.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>