sensor: Replace GpioLock with stdplus RAII helper

The old RAII helper was not move safe, although it was never moved in
the current code so it didn't have any effect on runtime safety.

Change-Id: Ica19ed7e60d699d86d0166b356cedb82e4a28b61
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/configure.ac b/configure.ac
index 289f34a..977594d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -31,6 +31,7 @@
 PKG_CHECK_MODULES([PHOSPHOR_DBUS_INTERFACES], [phosphor-dbus-interfaces])
 PKG_CHECK_MODULES([PHOSPHOR_LOGGING], [phosphor-logging])
 PKG_CHECK_MODULES([GPIOPLUS], [gpioplus])
+PKG_CHECK_MODULES([STDPLUS], [stdplus])
 # We need the header only CLI library
 AC_CHECK_HEADERS(
     [CLI/CLI.hpp],