projects/hdmi_text: Adjust build options to never promote globals

This never works and always produces worse results ... thins that
should be global should manually instanciate the SB_GB

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>

projects/hdmi_text/Makefile

@@ -13,7 +13,7 @@ BOARD ?= icebreaker
 DEVICE = up5k
 PACKAGE = sg48
 
-NEXTPNR_ARGS = --freq 75
+NEXTPNR_ARGS = --freq 75 --no-promote-globals
 
 # Include default rules
 include ../../build/project-rules.mk