crypto: caam - execute module exit point only if necessary

Commit 1b46c90c ("crypto: caam - convert top level drivers to libraries")
changed entry and exit points behavior for caamalg,
caamalg_qi, caamalg_qi2, caamhash, caampkc, caamrng.

For example, previously caam_pkc_init() and caam_pkc_exit() were
module entry/exit points. This means that if an error would happen
in caam_pkc_init(), then caam_pkc_exit() wouldn't have been called.
After the mentioned commit, caam_pkc_init() and caam_pkc_exit()
are manually called - from jr.c. caam_pkc_exit() is called
unconditionally, even if caam_pkc_init() failed.

Added a global variable to keep the status of the algorithm
registration and free of resources.
The exit point of caampkc/caamrng module is executed only if the
registration was successful. Therefore we avoid double free of
resources in case the algorithm registration failed.

Fixes: 1b46c90c ("crypto: caam - convert top level drivers to libraries")
Signed-off-by: Iuliana Prodan <iuliana.prodan@nxp.com>
Reviewed-by: Horia Geanta <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>