Rename relevant global symbols from size to bitlen

Just applying rename.pl with this file:

mbedtls_cipher_get_key_size mbedtls_cipher_get_key_bitlen
mbedtls_pk_get_size mbedtls_pk_get_bitlen
MBEDTLS_BLOWFISH_MIN_KEY MBEDTLS_BLOWFISH_MIN_KEY_BITS
MBEDTLS_BLOWFISH_MAX_KEY MBEDTLS_BLOWFISH_MAX_KEY_BITS
diff --git a/include/mbedtls/blowfish.h b/include/mbedtls/blowfish.h
index 74bbe26..a829d80 100644
--- a/include/mbedtls/blowfish.h
+++ b/include/mbedtls/blowfish.h
@@ -35,8 +35,8 @@
 
 #define MBEDTLS_BLOWFISH_ENCRYPT     1
 #define MBEDTLS_BLOWFISH_DECRYPT     0
-#define MBEDTLS_BLOWFISH_MAX_KEY     448
-#define MBEDTLS_BLOWFISH_MIN_KEY     32
+#define MBEDTLS_BLOWFISH_MAX_KEY_BITS     448
+#define MBEDTLS_BLOWFISH_MIN_KEY_BITS     32
 #define MBEDTLS_BLOWFISH_ROUNDS      16         /**< Rounds to use. When increasing this value, make sure to extend the initialisation vectors */
 #define MBEDTLS_BLOWFISH_BLOCKSIZE   8          /* Blowfish uses 64 bit blocks */