hw_wallet: don't make watching only if cannot pair

Instead issue a warning.  Being watching-only disables
various functionality that should instead just ask again
for the PIN to be input.

plugins/ledger/ledger.py

@@ -37,7 +37,6 @@ class BTChipWallet(BIP44_HW_Wallet):
         # device reconnects
         self.handler = None
         self.force_watching_only = False
-
         self.device_checked = False
         self.signing = False