Clean up some code

- Use good ELF technique in cosmo_dlopen()
- Make strerror() conform more to other libc impls
- Introduce __clear_cache() and use it in cosmo_dlopen()
- Remove libc/fmt/fmt.h header (trying to kill off LIBC_FMT)

tool/viz/basicidea.c

@@ -21,7 +21,6 @@
 #include "libc/calls/struct/stat.h"
 #include "libc/calls/struct/winsize.h"
 #include "libc/calls/termios.h"
-#include "libc/fmt/fmt.h"
 #include "libc/log/log.h"
 #include "libc/macros.internal.h"
 #include "libc/mem/mem.h"

tool/viz/derasterize.c

@@ -22,7 +22,6 @@
 #include "libc/calls/struct/stat.h"
 #include "libc/calls/termios.h"
 #include "libc/fmt/conv.h"
-#include "libc/fmt/fmt.h"
 #include "libc/limits.h"
 #include "libc/log/check.h"
 #include "libc/log/log.h"

tool/viz/dumphexc.c

@@ -16,7 +16,6 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/fmt/fmt.h"
 #include "libc/macros.internal.h"
 #include "libc/mem/mem.h"
 #include "libc/stdio/append.h"

tool/viz/life.c

@@ -24,7 +24,6 @@
 #include "libc/calls/termios.h"
 #include "libc/errno.h"
 #include "libc/fmt/conv.h"
-#include "libc/fmt/fmt.h"
 #include "libc/fmt/itoa.h"
 #include "libc/intrin/popcnt.h"
 #include "libc/intrin/safemacros.internal.h"

tool/viz/od16.c

@@ -18,7 +18,6 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/errno.h"
 #include "libc/fmt/conv.h"
-#include "libc/fmt/fmt.h"
 #include "libc/log/check.h"
 #include "libc/mem/mem.h"
 #include "libc/runtime/runtime.h"

tool/viz/printdos2errno.c

@@ -16,7 +16,6 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/fmt/fmt.h"
 #include "libc/fmt/magnumstrs.internal.h"
 #include "libc/intrin/dos2errno.internal.h"
 #include "libc/intrin/kprintf.h"

tool/viz/printvideo.c

@@ -41,7 +41,6 @@
 #include "libc/dns/dns.h"
 #include "libc/errno.h"
 #include "libc/fmt/conv.h"
-#include "libc/fmt/fmt.h"
 #include "libc/fmt/itoa.h"
 #include "libc/intrin/bits.h"
 #include "libc/intrin/kprintf.h"