[BUILD] fix the check for existence of symbolic link
[BUILD] fix the check for existence of symbolic link

Change-Id: I259d0473b61650552a70752a5c17239394996af8

cvramire/ARSDKBuildUtils,aoi/ARSDKBuildUtils,aoi/ARSDKBuildUtils,Parrot-Developers/ARSDKBuildUtils,pwkalana9/ARSDKBuildUtils,niavok/ARSDKBuildUtils,pwkalana9/ARSDKBuildUtils,Parrot-Developers/ARSDKBuildUtils,niavok/ARSDKBuildUtils,cvramire/ARSDKBuildUtils