lkmc_vector_equal into lkmc.c

Document lkmc.c

README.adoc

@@ -12990,6 +12990,23 @@ ls /mnt/9p/rootfs_overlay
 
 This way you can just hack away the scripts and try them out immediately without any further operations.
 
+==== lkmc.c
+
+The files:
+
+* link:lkmc.c[]
+* link:lkmc.h[]
+
+contain common C function helpers that can be used both in userland and baremetal. Oh, the infinite <<about-the-baremetal-setup,joys of Newlib>>.
+
+Those files also contain arch specific helpers under ifdefs like:
+
+....
+#if defined(__aarch64__)
+....
+
+We try to keep as much as possible in those files. It bloats builds a little, but just makes everything simpler to understand.
+
 === Test this repo
 
 ==== Automated tests