docs: minor fix of build emu

[no changelog]

docs/core/build/embedded.md

@@ -58,7 +58,7 @@ make vendor build_boardloader build_bootloader build_firmware
 Use `make upload` to upload the firmware to a production device.
 
 * For TT: Do not forget to [enter bootloader](https://www.youtube.com/watch?v=3hes1H4qRbw) on the device beforehand.
-* For TS3: You will have to [unlock bootloader] (https://trezor.io/learn/a/unlocking-the-bootloader-on-trezor-safe-3) first. Make sure to read the link in completeness for potentially unwanted effects.
+* For TS3: You will have to [unlock bootloader](https://trezor.io/learn/a/unlocking-the-bootloader-on-trezor-safe-3) first. Make sure to read the link in completeness for potentially unwanted effects.
 
 ## Flashing
 

docs/core/build/emulator.md

@@ -78,7 +78,8 @@ requires libclang for generating MicroPython FFI.
 Run the build with:
 
 ```sh
-make build_unix
+make build_unix                     # default
+make build_unix TREZOR_MODEL=R      # different model
 ```
 
 ## Run