* libc-{common,package}.bbclass: fix shlib renaming for the C library
Without this you'd end up with eglibc_2.12.ipk instead of libc6_2.12.ipk as before
* eglibc-locale: don't make versions go backwards after split from eglibc
eglibc was way beyond PR = "r1" at the time of the split, so increase PR to make package upgrades work
