Actually just use defmt-brtt without default features

Cargo.toml

@@ -7,11 +7,8 @@ version = "0.1.0"
 
 [dependencies]
 cortex-m = { version = "0.7", features = ["critical-section-single-core"] }
-defmt = "0.3"
-defmt-rtt = "0.4"
-# Use the logger below instead if you also want to use
-# non-RTT transports.
-# defmt-brtt = "0.1"
+defmt = { version = "0.3", features = ["encoding-rzcobs"]
+defmt-brtt = { version = "0.1", default-features = false, features = ["rtt"] }
 panic-probe = { version = "0.3", features = ["print-defmt"] }
 # TODO select the correct rtic backend
 rtic = { version = "2.0.0-alpha.1", features = [ "correct-rtic-backend" ] }