fix: cpufreqd MSR spam, udev-shim PCI spam, scheme throttle, keymaps dir

- cpufreqd: suppress MSR errors after 1 failure (was 10)
- udev-shim: demote PCI scan failures from WARN to DEBUG
- accessibility/ime/keymapd: throttle EBADF loop with 100ms sleep
- config: create /etc/keymaps directory for keymapd

local/recipes/system/redbear-accessibility/source/src/main.rs

@@ -1,6 +1,8 @@
 mod scheme;
 
 use std::io::Write;
+use std::thread;
+use std::time::Duration;
 
 use scheme::AccessibilityScheme;
 
@@ -23,8 +25,9 @@ fn main() {
                 break;
             }
             Err(e) => {
-                log_msg("ERROR", &format!("failed to read request: {}", e));
-                break;
+                log_msg("WARN", &format!("scheme read error (ignoring): {}", e));
+                thread::sleep(Duration::from_millis(100));
+                continue;
             }
         };