There is going to be no definitive answer for this.... because there is no standard repository of standard or acceptable flavors. You might want to check out DistroWatch.com for a list of a bunch of them.... but there's always going to be some random person out there working on some random permutation of Linux that's just a little bit different than everything else.
Linux.
Rather than listing them all here (which is subject to change), it would be better if you went to the web sites for the various flavors of Unix/Linux to check on what processors are supported.
Linux is only a Kernel (Operating System). Different Flavours of linux have different user programs on top of the same linux kernel. A high level example : Ubuntu has the user program(package) GNOME while Kubuntu has KDE, whereas both ubuntu & Kubuntu use the same Linux Kernel.
it is unknown how many flavors there are new flavors of cheese are being made all the time
maybe over a trillion flavors
there are 14 flavors.
See the link below for the answer.
I think it was the Linux kernel. There are many used with Linux now.
There are alleged to be 188 different flavors of gum.
46 flavors
46 flavors
at least two flavors