BUG/MEDIUM: backend: fix URI hash when a query string is present

Commit 98634f0 ("MEDIUM: backend: Enhance hash-type directive with an
algorithm options") cleaned up the hashing code by using a centralized
function. A bug appeared in get_server_uh() which is the URI hashing
function. Prior to the patch, the function would stop hashing on the
question mark, or on the trailing slash of a maximum directory count.
Consecutive to the patch, this last character is included into the
hash computation. This means that :

    GET /0
    GET /0?

Are not hashed similarly. The following configuration reproduces it :

    mode http
    balance uri
    server s1 redir /s1
    server s2 redir /s2

Many thanks to Vedran Furac for reporting this issue. The fix must
be backported to 1.5.
(cherry picked from commit fad4ffc89337277f3d5ed32b66986730e891558a)
1 file changed