Util: add function ffKernelModLoaded and use it

src/util/kernelMod.c

@@ -0,0 +1,39 @@
+#include "kernelMod.h"
+
+#if __linux__
+#include "common/io/io.h"
+
+bool ffKernelModLoaded(const char* modName)
+{
+    static FFstrbuf modules;
+    if (modules.chars == NULL)
+    {
+        ffStrbufInitS(&modules, "\n");
+        ffAppendFileBuffer("/proc/modules", &modules);
+    }
+
+    if (modules.length == 0) return false;
+
+    uint32_t len = (uint32_t) strlen(modName);
+    if (len > 250) return false;
+
+    char temp[256];
+    temp[0] = '\n';
+    memcpy(temp + 1, modName, len);
+    temp[1 + len] = ' ';
+    return memmem(modules.chars, modules.length, temp, len + 2) != NULL;
+}
+#elif __FreeBSD__
+#include <sys/param.h>
+#include <sys/module.h>
+
+bool ffKernelModLoaded(const char* modName)
+{
+    return modfind(modName) >= 0;
+}
+#else
+bool ffKernelModLoaded(FF_MAYBE_UNUSED const char* modName)
+{
+    return true; // Don't generate kernel module related errors
+}
+#endif