powerpc/crypto: Fix aes-gcm-p10 link errors

The recently added P10 AES/GCM code added some files containing
CRYPTOGAMS perl-asm code which are near duplicates of the p8 files
found in drivers/crypto/vmx.

In particular the newly added files produce functions with identical
names to the existing code.

When the kernel is built with CONFIG_CRYPTO_AES_GCM_P10=y and
CONFIG_CRYPTO_DEV_VMX_ENCRYPT=y that leads to link errors, eg:

  ld: drivers/crypto/vmx/aesp8-ppc.o: in function `aes_p8_set_encrypt_key':
  (.text+0xa0): multiple definition of `aes_p8_set_encrypt_key'; arch/powerpc/crypto/aesp8-ppc.o:(.text+0xa0): first defined here
  ...
  ld: drivers/crypto/vmx/ghashp8-ppc.o: in function `gcm_ghash_p8':
  (.text+0x140): multiple definition of `gcm_ghash_p8'; arch/powerpc/crypto/ghashp8-ppc.o:(.text+0x2e4): first defined here

Fix it for now by renaming the newly added files and functions to use
"p10" instead of "p8" in the names.

Fixes: 45a4672b

 ("crypto: p10-aes-gcm - Update Kconfig and Makefile")
Tested-by: Vishal Chourasia <vishalc@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230525150501.37081-1-mpe@ellerman.id.au