Multilib: Change profiling attribute to allow selection af arch

[thomas]

Currently you can either render the book to exclude or to include multilib instructions. That is kind of all or nothing.

We cannot render book to include instructions for -m32 only and leave out the -mx32 instruction or vice versa.

[thomas]

Fixed in r11571

$ make ARCH=ml_32 Render book including -m32 architecture

$ make ARCH=ml_x32 Render book including -mx32 architecture

$ make ARCH=ml_all Render book including both, -m32 and -mx32, architectures

[Bruce Dubbs]

Milestone renamed