Add embedded targets to docs.rs

Signed-off-by: Hugues de Valon <hugues.devalon@arm.com>

Author: hug-dev

Diff for: Cargo.toml

@@ -20,6 +20,16 @@ bare-metal = { version = "0.2.0", features = ["const-fn"] }
 volatile-register = "0.2.0"
 bitfield = "0.13.2"
 
+[package.metadata.docs.rs]
+targets = ["thumbv8m.main-none-eabihf",
+           "thumbv6m-none-eabi",
+           "thumbv7em-none-eabi",
+           "thumbv7em-none-eabihf",
+           "thumbv7m-none-eabi",
+           "thumbv8m.base-none-eabi",
+           "thumbv8m.main-none-eabi"
+]
+
 [features]
 cm7-r0p1 = []
 inline-asm = []