crypto: inside-secure - move the firmware to a better location

This patch moves the firmware loaded by the Inside Secure SafeXcel
driver from /lib/firmware/ to /lib/firmware/inside-secure/eip197b/. This
prepares the driver for future patches which will support other
revisions of the EIP197 crypto engine as they'll have their own
firmwares.

To keep the compatibility of what was done, the old path is still
supported as a fallback for the EIP197b (currently the only one
supported by the driver that loads a firmware).

Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>