refactor(measured-boot): change all occurrences of RSS to RSE

Changes all occurrences of "RSS" and "rss" in the code and build files
to "RSE" and "rse".

Signed-off-by: Tamas Ban <tamas.ban@arm.com>
Change-Id: I8c2fcbdf1de1c75f9969d28bc15e0b3500071404
diff --git a/drivers/measured_boot/rse/dice_prot_env.c b/drivers/measured_boot/rse/dice_prot_env.c
index 81a21d1..8e9185a 100644
--- a/drivers/measured_boot/rse/dice_prot_env.c
+++ b/drivers/measured_boot/rse/dice_prot_env.c
@@ -13,7 +13,7 @@
 
 #include <common/debug.h>
 #include <drivers/auth/crypto_mod.h>
-#include <drivers/measured_boot/rss/dice_prot_env.h>
+#include <drivers/measured_boot/rse/dice_prot_env.h>
 #include <lib/cassert.h>
 #include <lib/psa/dice_protection_environment.h>