Lately, it seems that for Carlos Santana, the cell phone has become as important an instrument as the guitar, what with the surfeit of guest stars that???ve peppered his albums since 1999???s multiplatinum ???Supernatural.??? This Gotham gig, a day-of-release one-off in support of the cameo-laden ???All That I Am??? (Arista), used such collaborations as an accent, rather than a main course ??? a c