Move cargo profile configuration to Cargo.toml

According to the Cargo book, profiles should be defined in `Cargo.toml`
(https://doc.rust-lang.org/cargo/reference/profiles.html).

Author: erdnaxe

.cargo/config

@@ -7,11 +7,3 @@ rustflags = [
 
 [build]
 target = "riscv32imac-unknown-none-elf"
-
-[profile.release]
-opt-level = "z"  # Optimize for size.
-codegen-units = 1
-lto = true
-
-[profile.dev]
-opt-level = "z"  # Optimize for size.

Cargo.toml

@@ -44,3 +44,10 @@ required-features = ["lcd"]
 name = "sdcard_test"
 required-features = ["sdcard"]
 
+[profile.release]
+opt-level = "z"  # Optimize for size.
+codegen-units = 1
+lto = true
+
+[profile.dev]
+opt-level = "z"  # Optimize for size.