Add USB DFU and OTG console SOC capability flags for esp32s2, esp32s3, and esp32p4.
Use these caps in Kconfig, documentation conditionals, and idf.py DFU actions so USB support
is derived from SOC capabilities instead of hardcoded target names.
Remove the internal fd table (fd_entry_t, is_fd_valid, fd_allows_read/write,
ESP_STDIO_BASIC_MODE tracking) from the console VFS.
Instead, console_open forwards directly to the primary backend's open_p,
so each open("/dev/console") creates a real fd in the underlying driver.
Read/write/fstat/fcntl/fsync all operate on the per-open fd from the
primary, not a stored init-time fd.
Structure:
- s_primary: separate variable for the primary backend entry
- s_auxiliary[]: slot-based array for auxiliary sinks (NULL = free)
- Scans all slots (no count variable) with NULL guards
- Auxiliaries opened lazily on first console open
- Closed when last console fd is closed (refcounted via s_open_count)
- Write and fsync fan-out protected by s_lock
esp_stdio contains everything the old esp_vfs_console contained (the vfs stdio glue layer)
as well as other functionality related to stdio (previously referred to as console)
igor.masar
Tomáš Rohlínek
Marius Vikhammer