doc/lightningd-config: precise alias are 32 __bytes__ long.

And not 32 characters long, as a character (for example 🐨) can be 4
bytes long.

Reported-By: Vasil Dimov <@vasild>

doc/lightningd-config.5

@@ -216,7 +216,7 @@ Note that once you encrypt the \fBhsm_secret\fR this option will be mandatory fo
 .SH Lightning node customization options
 
  \fBalias\fR=\fINAME\fR
-Up to 32 UTF-8 characters to tag your node\. Completely silly, since
+Up to 32 bytes of UTF-8 characters to tag your node\. Completely silly, since
 anyone can call their node anything they want\. The default is an
 NSA-style codename derived from your public key, but "Peter Todd" and
 "VAULTERO" are good options, too\.

doc/lightningd-config.5.md

@@ -173,7 +173,7 @@ Note that once you encrypt the `hsm_secret` this option will be mandatory for
 ### Lightning node customization options
 
  **alias**=*NAME*
-Up to 32 UTF-8 characters to tag your node. Completely silly, since
+Up to 32 bytes of UTF-8 characters to tag your node. Completely silly, since
 anyone can call their node anything they want. The default is an
 NSA-style codename derived from your public key, but "Peter Todd" and
 "VAULTERO" are good options, too.