fix(bsd): Correct architecture detection on *BSD

FreeBSD and NetBSD use uname -p for architecture detection.
Add BSD to the list of OSes that use this method.

Cherry-picked from dylanaraps#2191

Author: pkubaj

neofetch

@@ -1233,7 +1233,7 @@ get_distro() {
 
     # Get OS architecture.
     case $os in
-        Solaris|AIX|Haiku|IRIX|FreeMiNT)
+        Solaris|AIX|Haiku|IRIX|FreeMiNT|BSD)
             machine_arch=$(uname -p)
         ;;