powerpc: Rename copyuser_power7_vmx.c to vmx-helper.c

Subsequent patches will add more VMX library functions and it makes
sense to keep all the c-code helper functions in the one file.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
3 files changed