Initialize mbedtls_x509write_csr struct before USE_PSA_INIT(), mbedtls_x509write_csr_free() will crash if uninitialized
Initialize mbedtls_x509write_csr struct before USE_PSA_INIT(), mbedtls_x509write_csr_free() will crash if uninitialized

When USE_PSA_INIT() failed because lack of seedfile, mbedtls_x509write_csr_free()
crashed when called on an unitialized mbedtls_x509write_csr struct.

This moves mbedtls_x509write_csr_init before calling USE_PSA_INIT(),
which could probably fail, and uses the same flow in x509_csr_check()
and x509_csr_check_opaque().

Signed-off-by: Neil Armstrong <619b324efbf5f7848de055bdc8bef4c0dd7c8ef5@baylibre.com>

Mbed-TLS/mbedtls,Mbed-TLS/mbedtls,ARMmbed/mbedtls,ARMmbed/mbedtls,ARMmbed/mbedtls,ARMmbed/mbedtls,Mbed-TLS/mbedtls,Mbed-TLS/mbedtls