Fixes: #17612 : Update ASN types in asn.md (#17625)

* Update asn.md

There are no 64-bit AS Numbers - 16- and 32-bit only :
https://www.iana.org/assignments/as-numbers/as-numbers.xhtml

* Update docs/models/ipam/asn.md

Co-authored-by: bluikko <14869000+bluikko@users.noreply.github.com>

---------

Co-authored-by: bluikko <14869000+bluikko@users.noreply.github.com>

docs/models/ipam/asn.md

@@ -1,6 +1,6 @@
 # ASNs
 
-An Autonomous System Number (ASN) is a numeric identifier used in the BGP protocol to identify which [autonomous system](https://en.wikipedia.org/wiki/Autonomous_system_%28Internet%29) a particular prefix is originating and transiting through. NetBox support both 32- and 64- ASNs.
+An Autonomous System Number (ASN) is a numeric identifier used in the Border Gateway Protocol (BGP) to identify which [autonomous system](https://en.wikipedia.org/wiki/Autonomous_system_%28Internet%29) a particular prefix is originating from or transiting through. NetBox supports both 16- and 32-bit ASNs.
 
 ASNs must be globally unique within NetBox, and may be allocated from within a [defined range](./asnrange.md). Each ASN may be assigned to multiple [sites](../dcim/site.md).
 
@@ -8,7 +8,7 @@ ASNs must be globally unique within NetBox, and may be allocated from within a [
 
 ### AS Number
 
-The 32- or 64-bit AS number.
+The 16- or 32-bit AS number.
 
 ### RIR