recovery: initialize keys press tracking status

Checks for keys pressed return random results because of an uninitialized data
structure.

Change-Id: Ic8b3d453d62347921aa893403079b374c16a092e
Signed-off-by: Mihai Serban <mihai.serban@intel.com>
diff --git a/ui.cpp b/ui.cpp
index 5043ee5..a7c8bea 100644
--- a/ui.cpp
+++ b/ui.cpp
@@ -55,6 +55,7 @@
     pthread_mutex_init(&key_queue_mutex, NULL);
     pthread_cond_init(&key_queue_cond, NULL);
     self = this;
+    memset(key_pressed, 0, sizeof(key_pressed));
 }
 
 void RecoveryUI::Init() {