Address GitHub feedback

- Defer registry close calls
- Ensure size parameter in GetComputerName is properly specified
- Clean up some comments to ensure correctness

Signed-off-by: Ben Ridley <benridley29@gmail.com>

headers/sysinfoapi/sysinfoapi.go

@@ -148,12 +148,12 @@ func GetSystemInfo() SystemInfo {
 }
 
 // GetComputerName wraps the GetComputerNameW function in a more Go-like way
-// https://docs.microsoft.com/en-us/windows/win32/api/winbase/nf-winbase-getcomputernamew
+// https://docs.microsoft.com/en-us/windows/win32/api/sysinfoapi/nf-sysinfoapi-getcomputernameexw
 func GetComputerName(f WinComputerNameFormat) (string, error) {
 	// 1kb buffer to accept computer name. This should be more than enough as the maximum size
 	// returned is the max length of a DNS name, which this author believes is 253 characters.
 	size := 1024
-	var buffer [4096]uint16
+	var buffer [1024]uint16
 	r1, _, err := procGetComputerNameExW.Call(uintptr(f), uintptr(unsafe.Pointer(&buffer)), uintptr(unsafe.Pointer(&size)))
 	if r1 == 0 {
 		return "", err