uclient: Update to 2016-12-09

Brings in the following changes:

52d955fd802a remove obsolete mac os x /opt/local include/library search path
a4e49b4163b2 Fix unused results warnings
48cfff3fbec9 uclient-http: send correct "Host:" header if port is set

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>