Fix cat and wc

Trying to fit 64K onto stack was a bad idea.

src/user/app/cat/cat.c

@@ -5,7 +5,7 @@
 #define BLOCK_SIZE 65536
 
 exit_code_t pass(uint64_t fd) {
-  char buffer[BLOCK_SIZE];
+  static char buffer[BLOCK_SIZE];
   uint64_t bytes;
   while ((bytes = read(fd, BLOCK_SIZE, buffer))) {
     if (bytes == (uint64_t)-1) {

src/user/app/wc/wc.c

@@ -6,7 +6,7 @@
 #define BLOCK_SIZE 65536
 
 exit_code_t pass(uint64_t fd) {
-  char buffer[BLOCK_SIZE];
+  static char buffer[BLOCK_SIZE];
   uint64_t bytes;
   uint64_t total = 0;
   while ((bytes = read(fd, BLOCK_SIZE, buffer))) {