Remove unused definition

PSA defines CBC with no padding, and CBC with PKCS7 padding.  The bare
"ALG_CBC" is not defined, so remove this definition.

Signed-off-by: David Brown <david.brown@linaro.org>
diff --git a/include/psa/crypto_config.h b/include/psa/crypto_config.h
index 0fa1b13..a6cc07a 100644
--- a/include/psa/crypto_config.h
+++ b/include/psa/crypto_config.h
@@ -50,7 +50,6 @@
 #ifndef PSA_CRYPTO_CONFIG_H
 #define PSA_CRYPTO_CONFIG_H
 
-#define PSA_WANT_ALG_CBC                        1
 #define PSA_WANT_ALG_CBC_NO_PADDING             1
 #define PSA_WANT_ALG_CBC_PKCS7                  1
 #define PSA_WANT_ALG_CFB                        1