Update toolchain, get rid of the std-features hack

The `compiler-builtins-mangled-names` thingie¹ is no longer needed,
since `compiler_builtins` has been improved to avoid pulling the
problematic functions:

- rust-lang/compiler-builtins#462
- rust-lang/compiler-builtins#466
- rust-lang/rust#97435

¹ rust-lang/rust#82242

Suggested-by: @Patryk27
Link: Rahix/avr-hal-template#8

Author: Rahix

examples/arduino-diecimila/.cargo/config.toml

@@ -6,4 +6,3 @@ runner = "ravedude diecimila"
 
 [unstable]
 build-std = ["core"]
-build-std-features = ["compiler-builtins-mangled-names"]

examples/arduino-leonardo/.cargo/config.toml

@@ -6,4 +6,3 @@ runner = "ravedude leonardo"
 
 [unstable]
 build-std = ["core"]
-build-std-features = ["compiler-builtins-mangled-names"]

examples/arduino-mega2560/.cargo/config.toml

@@ -6,4 +6,3 @@ runner = "ravedude -cb 57600 mega2560"
 
 [unstable]
 build-std = ["core"]
-build-std-features = ["compiler-builtins-mangled-names"]

examples/arduino-nano/.cargo/config.toml

@@ -6,4 +6,3 @@ runner = "ravedude nano -cb 57600"
 
 [unstable]
 build-std = ["core"]
-build-std-features = ["compiler-builtins-mangled-names"]

examples/arduino-uno/.cargo/config.toml

@@ -6,4 +6,3 @@ runner = "ravedude uno -cb 57600"
 
 [unstable]
 build-std = ["core"]
-build-std-features = ["compiler-builtins-mangled-names"]

examples/nano168/.cargo/config.toml

@@ -6,4 +6,3 @@ runner = "ravedude nano168 -cb 57600"
 
 [unstable]
 build-std = ["core"]
-build-std-features = ["compiler-builtins-mangled-names"]

examples/sparkfun-promicro/.cargo/config.toml

@@ -6,4 +6,3 @@ runner = "ravedude promicro"
 
 [unstable]
 build-std = ["core"]
-build-std-features = ["compiler-builtins-mangled-names"]

examples/trinket-pro/.cargo/config.toml

@@ -6,4 +6,3 @@ runner = "ravedude trinket-pro"
 
 [unstable]
 build-std = ["core"]
-build-std-features = ["compiler-builtins-mangled-names"]

examples/trinket/.cargo/config.toml

@@ -6,4 +6,3 @@ runner = "ravedude trinket"
 
 [unstable]
 build-std = ["core"]
-build-std-features = ["compiler-builtins-mangled-names"]

rust-toolchain.toml

@@ -1,4 +1,4 @@
 [toolchain]
-channel = "nightly-2022-05-10"
+channel = "nightly-2022-06-13"
 components = [ "rust-src" ]
 profile = "minimal"