[TS-5024] Ran clang-format. Modify TSHttpTxnHookAdd to add hook only once.
[TS-5024] Ran clang-format.
Modify TSHttpTxnHookAdd to add hook only once.

Change-Id: I737ca666cc05f2e2e2006cbef7f6b5a68b0eb71f

PSUdaemon/trafficserver,duke8253/trafficserver,dyrock/trafficserver,davidbz/trafficserver,clearswift/trafficserver,reveller/trafficserver,reveller/trafficserver,SolidWallOfCode/trafficserver,vmamidi/trafficserver,PSUdaemon/trafficserver,duke8253/trafficserver,chitianhao/trafficserver,persiaAziz/trafficserver,bryancall/trafficserver,dyrock/trafficserver,persiaAziz/trafficserver,rpufky/trafficserver,vmamidi/trafficserver,reveller/trafficserver,chitianhao/trafficserver,dyrock/trafficserver,persiaAziz/trafficserver,clearswift/trafficserver,dyrock/trafficserver,chenglongwei/trafficserver,PSUdaemon/trafficserver,clearswift/trafficserver,davidbz/trafficserver,vmamidi/trafficserver,rahmalik/trafficserver,duke8253/trafficserver,pbchou/trafficserver,rahmalik/trafficserver,rpufky/trafficserver,davidbz/trafficserver,SolidWallOfCode/trafficserver,duke8253/trafficserver,reveller/trafficserver,pbchou/trafficserver,bryancall/trafficserver,chenglongwei/trafficserver,rahmalik/trafficserver,clearswift/trafficserver,chitianhao/trafficserver,SolidWallOfCode/trafficserver,chenglongwei/trafficserver,persiaAziz/trafficserver,taoyunxing/trafficserver,chitianhao/trafficserver,rahmalik/trafficserver,taoyunxing/trafficserver,dyrock/trafficserver,davidbz/trafficserver,rahmalik/trafficserver,pbchou/trafficserver,reveller/trafficserver,clearswift/trafficserver,SolidWallOfCode/trafficserver,vmamidi/trafficserver,chenglongwei/trafficserver,chitianhao/trafficserver,PSUdaemon/trafficserver,persiaAziz/trafficserver,duke8253/trafficserver,taoyunxing/trafficserver,rahmalik/trafficserver,SolidWallOfCode/trafficserver,rpufky/trafficserver,rpufky/trafficserver,PSUdaemon/trafficserver,rahmalik/trafficserver,bryancall/trafficserver,taoyunxing/trafficserver,chenglongwei/trafficserver,persiaAziz/trafficserver,pbchou/trafficserver,taoyunxing/trafficserver,persiaAziz/trafficserver,PSUdaemon/trafficserver,rpufky/trafficserver,clearswift/trafficserver,SolidWallOfCode/trafficserver,dyrock/trafficserver,bryancall/trafficserver,SolidWallOfCode/trafficserver,clearswift/trafficserver,reveller/trafficserver,davidbz/trafficserver,rpufky/trafficserver,chenglongwei/trafficserver,rpufky/trafficserver,chenglongwei/trafficserver,rahmalik/trafficserver,bryancall/trafficserver,taoyunxing/trafficserver,davidbz/trafficserver,rpufky/trafficserver,bryancall/trafficserver,clearswift/trafficserver,pbchou/trafficserver,vmamidi/trafficserver,persiaAziz/trafficserver,duke8253/trafficserver,dyrock/trafficserver,taoyunxing/trafficserver,reveller/trafficserver,PSUdaemon/trafficserver,chenglongwei/trafficserver,vmamidi/trafficserver,clearswift/trafficserver,pbchou/trafficserver,reveller/trafficserver,PSUdaemon/trafficserver,rahmalik/trafficserver,duke8253/trafficserver,chitianhao/trafficserver,PSUdaemon/trafficserver,reveller/trafficserver,rpufky/trafficserver,chitianhao/trafficserver,taoyunxing/trafficserver,taoyunxing/trafficserver