meta-facebook: phosphor-sel-logger: Use packageconfig

This makes it possible for us to change out build specific settings.

Change-Id: Iebcf178e7f392381d06480c72a193907b3a61f96
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/meta-facebook/recipes-phosphor/sel-logger/phosphor-sel-logger_%.bbappend b/meta-facebook/recipes-phosphor/sel-logger/phosphor-sel-logger_%.bbappend
index 4948cb4..ac98c7c 100644
--- a/meta-facebook/recipes-phosphor/sel-logger/phosphor-sel-logger_%.bbappend
+++ b/meta-facebook/recipes-phosphor/sel-logger/phosphor-sel-logger_%.bbappend
@@ -1,3 +1 @@
-# Enable threshold monitoring
-EXTRA_OECMAKE += "-DSEL_LOGGER_MONITOR_THRESHOLD_EVENTS=ON"
-EXTRA_OECMAKE += "-DREDFISH_LOG_MONITOR_PULSE_EVENTS=ON"
+PACKAGECONFIG_append = " log-threshold log-pulse"