meta-facebook: reduce permissions on scripts

Scripts should be installed with 0755 permissions and not 0777,
otherwise non-root users can potentially modify or delete them.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I41270a2bb3fb940d8ca49ed6230545d98efb2fea
diff --git a/meta-facebook/recipes-phosphor/fans/phosphor-fan_%.bbappend b/meta-facebook/recipes-phosphor/fans/phosphor-fan_%.bbappend
index e9dcf33..819903a 100644
--- a/meta-facebook/recipes-phosphor/fans/phosphor-fan_%.bbappend
+++ b/meta-facebook/recipes-phosphor/fans/phosphor-fan_%.bbappend
@@ -31,7 +31,7 @@
     install -m 0755 -d ${D}/var/lib/phosphor-fan-presence/sensor-monitor
 
     install -d ${D}${libexecdir}/phosphor-fan-sensor-monitor
-    install -m 0777 ${WORKDIR}/host-poweroff ${D}${libexecdir}/phosphor-fan-sensor-monitor/
+    install -m 0755 ${WORKDIR}/host-poweroff ${D}${libexecdir}/phosphor-fan-sensor-monitor/
 }
 
 pkg_postinst:${PN}-sensor-monitor() {