Fix build break on dependency from CRYPTO

I got a message from random config robot that he found a build break... It happens because certain modules which are compiled as builtin depends on CRYPTO=m and select required components as modules instead of making them builtin. Here is couple of patches to fix it.

config: i386-randconfig-c1-07060441 (attached as .config)

All error/warnings:

security/built-in.o: In function `asymmetric_verify':

security/built-in.o: In function `asymmetric_verify':

         crypto/built-in.o: In function `public_key_destroy':
    >> (.text+0x383): undefined reference to `mpi_free'
	    crypto/built-in.o: In function `RSA_verify_signature':
    >> rsa.c:(.text+0x474): undefined reference to `mpi_get_nbits'
    >> rsa.c:(.text+0x481): undefined reference to `mpi_get_nbits'
    >> rsa.c:(.text+0x491): undefined reference to `mpi_cmp_ui'
    >> rsa.c:(.text+0x49f): undefined reference to `mpi_cmp'
    >> rsa.c:(.text+0x4aa): undefined reference to `mpi_alloc'
    >> rsa.c:(.text+0x4c4): undefined reference to `mpi_powm'
    >> rsa.c:(.text+0x4d2): undefined reference to `mpi_free'
    >> rsa.c:(.text+0x4f1): undefined reference to `mpi_free'
    >> rsa.c:(.text+0x52e): undefined reference to `mpi_get_nbits'
    >> rsa.c:(.text+0x54a): undefined reference to `mpi_get_buffer'
    >> rsa.c:(.text+0x5fb): undefined reference to `__crypto_memneq'
    >> rsa.c:(.text+0x618): undefined reference to `__crypto_memneq'
       crypto/built-in.o: In function `x509_free_certificate':
    >> (.text+0x90a): undefined reference to `mpi_free'
         crypto/built-in.o: In function `x509_cert_parse':
    >> (.text+0x986): undefined reference to `asn1_ber_decoder'
      crypto/built-in.o: In function `x509_cert_parse':
    >> (.text+0x9a1): undefined reference to `asn1_ber_decoder'
        crypto/built-in.o: In function `x509_note_OID':
    >> (.text+0x9e4): undefined reference to `look_up_OID'
	   crypto/built-in.o: In function `x509_note_OID':

crypto/built-in.o: In function `rsa_extract_mpi':

- Dmitry

Dmitry Kasatkin (2):
asymmetric_keys: make crypto builtin if asymmetric keys selected as
builtin
digsig: make crypto builtin if digsig selected as builtin

 crypto/Kconfig                 | 6 +++++-
 crypto/asymmetric_keys/Kconfig | 2 ++
 lib/Kconfig                    | 3 ++-
 3 files changed, 9 insertions(+), 2 deletions(-)

1.9.1