posix: fcntl.h: define constants to agree with picolibc
PicoLibC defines `O_CREAT` (really `_FCREAT`) as 0x0040.
Otherwise, these constants are identical.
#ifndef ZEPHYR_POSIX_FCNTL_H_
#define ZEPHYR_POSIX_FCNTL_H_
+#ifdef CONFIG_PICOLIBC
+#define O_CREAT 0x0040
+#else
#define O_CREAT 0x0200
+#endif
+
#define O_APPEND 0x0400
#define O_EXCL 0x0800
#define O_NONBLOCK 0x4000
