Add a comment to fix the docker issue (#442)

* Add a comment to fix the docker issue

Fixing #2694
Which was caused by moby/moby#38072
Fixing by changing file size. Previously the change from 0 to 1
didn't change the file size, and docker squish optimized the change
out.

Author: pavel-shirshov

debian/rules

@@ -55,7 +55,7 @@ override_dh_auto_configure:
 override_dh_install:
 	dh_install
 ifeq ($(shell cat /tmp/syncd-build), --enable-rpcserver=yes)
-	sed -i 's/ENABLE_SAITHRIFT=0/ENABLE_SAITHRIFT=1/' debian/syncd-rpc/usr/bin/syncd_init_common.sh
+	sed -i 's|ENABLE_SAITHRIFT=0|ENABLE_SAITHRIFT=1 # Add a comment to fix https://github.com/Azure/sonic-buildimage/issues/2694 |' debian/syncd-rpc/usr/bin/syncd_init_common.sh
 endif
 
 override_dh_installinit: