Fold conv package into fmt

Both packages had nearly identical dependency requirements, so merging
them should help reduce the complexity of the build graph.

tool/viz/lib/formatmatrix-double.c

@@ -18,7 +18,7 @@
 │ 02110-1301 USA                                                               │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/assert.h"
-#include "libc/conv/conv.h"
+#include "libc/fmt/conv.h"
 #include "libc/log/check.h"
 #include "libc/math.h"
 #include "libc/mem/mem.h"

tool/viz/lib/formatstringtable-assembly.c

@@ -19,7 +19,7 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/bits/bits.h"
 #include "libc/bits/safemacros.internal.h"
-#include "libc/conv/itoa.h"
+#include "libc/fmt/itoa.h"
 #include "libc/runtime/gc.h"
 #include "libc/str/str.h"
 #include "libc/unicode/unicode.h"

tool/viz/lib/formatstringtable-code.c

@@ -18,7 +18,7 @@
 │ 02110-1301 USA                                                               │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/bits/safemacros.internal.h"
-#include "libc/conv/itoa.h"
+#include "libc/fmt/itoa.h"
 #include "tool/viz/lib/formatstringtable.h"
 
 void *FormatStringTableAsCode(long yn, long xn, const char *const T[yn][xn],

tool/viz/lib/vizlib.mk

@@ -25,27 +25,26 @@ TOOL_VIZ_LIB_A_OBJS =					\
 	$(TOOL_VIZ_LIB_A_SRCS_C:%.c=o/$(MODE)/%.o)
 
 TOOL_VIZ_LIB_A_DIRECTDEPS =				\
-	DSP_TTY						\
 	DSP_CORE					\
 	DSP_SCALE					\
-	LIBC_INTRIN					\
+	DSP_TTY						\
 	LIBC_ALG					\
 	LIBC_BITS					\
 	LIBC_CALLS					\
-	LIBC_CONV					\
 	LIBC_FMT					\
-	LIBC_SYSV					\
-	LIBC_UNICODE					\
-	LIBC_TESTLIB					\
+	LIBC_INTRIN					\
+	LIBC_LOG					\
 	LIBC_MEM					\
 	LIBC_NEXGEN32E					\
 	LIBC_RUNTIME					\
-	LIBC_LOG					\
+	LIBC_STDIO					\
+	LIBC_STR					\
+	LIBC_STUBS					\
+	LIBC_SYSV					\
+	LIBC_TESTLIB					\
 	LIBC_TIME					\
 	LIBC_TINYMATH					\
-	LIBC_STDIO					\
-	LIBC_STUBS					\
-	LIBC_STR					\
+	LIBC_UNICODE					\
 	LIBC_X						\
 	THIRD_PARTY_AVIR				\
 	THIRD_PARTY_GDTOA				\