perf symbols: Make the kallsyms loading routines part of the dso class
perf symbols: Make the kallsyms loading routines part of the dso class

So that the kallsyms loading routines are the direct counterpart
of the vmlinux loading ones, i.e. dso__load_kallsyms is the
counterpart of dso__load_vmlinux.

In the process make them also use the symbols rb tree indexed by
map->type, paving the way for supporting other types of symtabs,
such as the next one to be supported: variables.

This also allowed removal of yet another global variable:
kernel_map__functions.

Signed-off-by: Arnaldo Carvalho de Melo <293abb6b76d7791c0732cc517d38c4b5c734b87f@redhat.com>
Cc: Frédéric Weisbecker <e8a1bf9163cb25e93cfd6540f223b3872ea7ee55@gmail.com>
Cc: Mike Galbraith <3cfa3897b7f55b5396b7a47c83b66325184bc9b4@gmx.de>
Cc: Peter Zijlstra <645ca7d3a8d3d4f60557176cd361ea8351edc32b@chello.nl>
Cc: Paul Mackerras <19a0ba370c443ba08d20b5061586430ab449ee8c@samba.org>
LKML-Reference: <62adb0983aa62d35f6f80346d5b9edf6bd4ef23a@infradead.org>
Signed-off-by: Ingo Molnar <9dbbbf0688fedc85ad4da37637f1a64b8c718ee2@elte.hu>

TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs