arch: powerpc: Stop building and using oprofile

The "oprofile" user-space tools don't use the kernel OPROFILE support
any more, and haven't in a long time. User-space has been converted to
the perf interfaces.

This commits stops building oprofile for powerpc and removes any
reference to it from directories in arch/powerpc/ apart from
arch/powerpc/oprofile, which will be removed in the next commit (this is
broken into two commits as the size of the commit became very big, ~5k
lines).

Note that the member "oprofile_cpu_type" in "struct cpu_spec" isn't
removed as it was also used by other parts of the code.

Suggested-by: Christoph Hellwig <hch@infradead.org>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Robert Richter <rric@kernel.org>
Acked-by: William Cohen <wcohen@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Thomas Gleixner <tglx@linutronix.de>

arch/powerpc/configs/ppc64e_defconfig

@@ -14,7 +14,6 @@ CONFIG_CPUSETS=y
 CONFIG_BLK_DEV_INITRD=y
 # CONFIG_COMPAT_BRK is not set
 CONFIG_PROFILING=y
-CONFIG_OPROFILE=y
 CONFIG_MODULES=y
 CONFIG_MODULE_UNLOAD=y
 CONFIG_MODVERSIONS=y