tools/mm: fix build warnings with musl-libc

musl-libc warns about the following:

/home/florian/dev/buildroot/output/arm64/rpi4-b/host/aarch64-buildroot-linux-musl/sysroot/usr/include/sys/errno.h:1:2: attention: #warning redirecting incorrect #include <sys/errno.h> to <errno.h> [-Wcpp]
1 | #warning redirecting incorrect #include <sys/errno.h> to <errno.h>
| ^~~~~~~
/home/florian/dev/buildroot/output/arm64/rpi4-b/host/aarch64-buildroot-linux-musl/sysroot/usr/include/sys/fcntl.h:1:2: attention: #warning redirecting incorrect #include <sys/fcntl.h> to <fcntl.h> [-Wcpp]
1 | #warning redirecting incorrect #include <sys/fcntl.h> to <fcntl.h>
| ^~~~~~~

include errno.h and fcntl.h directly.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Florian Fainelli <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>

tools/mm/page-types.c

···
 #include <signal.h>
 #include <inttypes.h>
 #include <sys/types.h>
-#include <sys/errno.h>
-#include <sys/fcntl.h>
+#include <errno.h>
+#include <fcntl.h>
 #include <sys/mount.h>
 #include <sys/statfs.h>
 #include <sys/mman.h>