examples/gnrc_networking: fix comments

As the lines refered to in the comments are already commented out,
the correct thing to do to use them is to uncomment them.

examples/gnrc_networking/Makefile

@@ -40,13 +40,13 @@ USEMODULE += netstats_rpl
 # development process:
 CFLAGS += -DDEVELHELP
 
-# Comment the following 2 lines out to specify static link lokal IPv6 address
-# this might be useful for testing, in cases whre you cannot or do not want to
+# Uncomment the following 2 lines to specify static link lokal IPv6 address
+# this might be useful for testing, in cases where you cannot or do not want to
 # run a shell with ifconfig to get the real link lokal address.
 #IPV6_STATIC_LLADDR ?= '"fe80::cafe:cafe:cafe:1"'
 #CFLAGS += -DGNRC_IPV6_STATIC_LLADDR=$(IPV6_STATIC_LLADDR)
 
-# Comment this out to join RPL DODAGs even if DIOs do not contain
+# Uncomment this to join RPL DODAGs even if DIOs do not contain
 # DODAG Configuration Options (see the doc for more info)
 # CFLAGS += -DGNRC_RPL_DODAG_CONF_OPTIONAL_ON_JOIN