bionic: remove unneeded variable from chk_realloc()

... and simplify the generated code.

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
diff --git a/libc/bionic/malloc_leak.c b/libc/bionic/malloc_leak.c
index 305f954..ad1d2b4 100644
--- a/libc/bionic/malloc_leak.c
+++ b/libc/bionic/malloc_leak.c
@@ -665,8 +665,9 @@
     }
 
     if (new_buffer) {
-        size_t size = (bytes < old_bytes)?(bytes):(old_bytes);
-        memcpy(new_buffer, mem, size);
+        if (bytes > old_bytes)
+            bytes = old_bytes;
+        memcpy(new_buffer, mem, bytes);
         chk_free(mem);
     }