chore(style): apply flake8 findings on site_scons python files

[no changelog]

core/site_scons/boards/trezor_r_v10.py

@@ -35,7 +35,7 @@ def configure(
     defines += [f"HW_REVISION={hw_revision}"]
     sources += [f"embed/trezorhal/stm32f4/displays/{display}"]
 
-    sources += [f"embed/trezorhal/stm32f4/i2c.c"]
+    sources += ["embed/trezorhal/stm32f4/i2c.c"]
 
     if "input" in features_wanted:
         sources += ["embed/trezorhal/stm32f4/button.c"]

core/site_scons/boards/trezor_t.py

@@ -35,18 +35,18 @@ def configure(
     defines += [f"HW_MODEL={hw_model}"]
     defines += [f"HW_REVISION={hw_revision}"]
     sources += [f"embed/trezorhal/stm32f4/displays/{display}"]
-    sources += [f"embed/trezorhal/stm32f4/backlight_pwm.c"]
+    sources += ["embed/trezorhal/stm32f4/backlight_pwm.c"]
     sources += [
-        f"embed/trezorhal/stm32f4/displays/panels/tf15411a.c",
+        "embed/trezorhal/stm32f4/displays/panels/tf15411a.c",
     ]
     sources += [
-        f"embed/trezorhal/stm32f4/displays/panels/154a.c",
+        "embed/trezorhal/stm32f4/displays/panels/154a.c",
     ]
     sources += [
-        f"embed/trezorhal/stm32f4/displays/panels/lx154a2411.c",
+        "embed/trezorhal/stm32f4/displays/panels/lx154a2411.c",
     ]
     sources += [
-        f"embed/trezorhal/stm32f4/displays/panels/lx154a2422.c",
+        "embed/trezorhal/stm32f4/displays/panels/lx154a2422.c",
     ]
 
     features_available.append("backlight")