sysctl: Use /sys/kernel/variables/ directory instead of /proc/sys

Author: https://github.com/supercomputer7
Commit: a0ed543993
Pull-request: https://github.com/SerenityOS/serenity/pull/15593
Reviewed-by: https://github.com/ADKaster ✅
Reviewed-by: https://github.com/kleinesfilmroellchen ✅

Base/usr/share/man/man8/sysctl.md

@@ -12,7 +12,7 @@ sysctl - configure kernel parameters at runtime
 
 sysctl is a utility for managing kernel configuration parameters at runtime.
 This requires root privileges, and can crash your system.
-Available parameters are listed under /proc/sys/.
+Available parameters are listed under /sys/kernel/variables/.
 
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