HCI: Fix improper rfkill handling

Current behavior with kernel rfkill module loaded produces a cascade of
crash events starting from the following logcat error:

    unable to bind bluetooth user channel: Operation not possible due to RF-kill

However, the same device configuration worked well with btlinux HAL,
which I assume was used as a base for this HAL.

After some investigation, I found that the rfkill(1) function call in the
btlinux call changed the state to 1, which is RFKILL_STATE_UNBLOCKED.
The current rfkill(1) sets the soft block value to 1, which corresponds
to the state value 0 (RFKILL_STATE_SOFT_BLOCKED).

Fix it by providing the correct values to the rfkill() call.

Change-Id: I7a62744f9c21d80b9f8fa37f6c172afa2a5b6c8a
Signed-off-by: Roman Stratiienko <r.stratiienko@gmail.com>
diff --git a/bluetooth/aidl/default/net_bluetooth_mgmt.cpp b/bluetooth/aidl/default/net_bluetooth_mgmt.cpp
index 24693ef..6b0cd63 100644
--- a/bluetooth/aidl/default/net_bluetooth_mgmt.cpp
+++ b/bluetooth/aidl/default/net_bluetooth_mgmt.cpp
@@ -259,8 +259,8 @@
 int NetBluetoothMgmt::openHci(int hci_interface) {
   ALOGI("opening hci interface %d", hci_interface);
 
-  // Block Bluetooth.
-  rfkill(1);
+  // Unblock Bluetooth.
+  rfkill(0);
 
   // Wait for the HCI interface to complete initialization or to come online.
   int hci = waitHciDev(hci_interface);
@@ -300,8 +300,8 @@
     bt_fd_ = -1;
   }
 
-  // Unblock Bluetooth.
-  rfkill(0);
+  // Block Bluetooth.
+  rfkill(1);
 }
 
 }  // namespace aidl::android::hardware::bluetooth::impl