Merge branch 'ps-devel-fix-thread-less-compile-001' into 'master'

genesys: use usleep instead of std::this_thread::sleep_for to re-enable thread less compile

See merge request sane-project/backends!619

backend/genesys/scanner_interface_usb.cpp

@@ -43,7 +43,6 @@
 
 #include "scanner_interface_usb.h"
 #include "low.h"
-#include <thread>
 
 namespace genesys {
 
@@ -481,7 +480,7 @@ void ScannerInterfaceUsb::sleep_us(unsigned microseconds)
     if (sanei_usb_is_replay_mode_enabled()) {
         return;
     }
-    std::this_thread::sleep_for(std::chrono::microseconds{microseconds});
+    usleep(microseconds);
 }
 
 void ScannerInterfaceUsb::record_progress_message(const char* msg)