crypto: stm32 - solve crc issue during unbind

Use the correct unregister_shashes function to
to remove the registered algo

Signed-off-by: Lionel Debieve <lionel.debieve@st.com>
Reviewed-by: Fabien Dessenne <fabien.dessenne@st.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>