`embassy-nxp`: make `defmt` optional

also enable it on all dependencies (where available).

this is needed because in a next commit we'll add code to
`embassy-hal-internal` which uses the feature in a macro, as it expects
`defmt` to be optional in all embassy HALs. this was the only HAL where
that wasn't the case.

note that this is a breaking change for consumers! if you wish to use
`defmt` in `embassy-nxp` you now need to enable the feature.

1 files changed, 5 insertions, 2 deletions

diff --git a/embassy-nxp/Cargo.toml b/embassy-nxp/Cargo.toml
index cf36a67ec..031cd4aba 100644
--- a/embassy-nxp/Cargo.toml
+++ b/embassy-nxp/Cargo.toml
@@ -10,8 +10,11 @@ critical-section = "1.1.2"
 embassy-hal-internal = { version = "0.2.0", path = "../embassy-hal-internal", features = ["cortex-m", "prio-bits-2"] }
 embassy-sync = { version = "0.6.2", path = "../embassy-sync" }
 lpc55-pac = "0.5.0"
-defmt = "0.3.8"
+defmt = { version = "0.3.8", optional = true }
 
 [features]
 default = ["rt"]
-rt = ["lpc55-pac/rt"]
\ No newline at end of file
+rt = ["lpc55-pac/rt"]
+
+## Enable [defmt support](https://docs.rs/defmt) and enables `defmt` debug-log messages and formatting in embassy drivers.
+defmt = ["dep:defmt", "embassy-hal-internal/defmt", "embassy-sync/defmt"]