Build Targets ISA

Hi,

I like to suggest that LEDE changes the build target from mips24kc to mips32r2.
The reason why is because it is confusing.
On x86 system is is exactly the same.
GCC have specific targets like westmere, prescott, ivybridge etc BUT you never see packages for x86 being branded as busybox.westmere instead it is always busybox.x86_64 and busybox.x86 or busybox.amd64
Same concept mips32r2 is the ISA so all the packages should be build with that tag with big and little endian versions.

mips32r2 should be the ISA with either be (big endian) atheros mips or el (endian little) ralink mips