modules/lib/picolibc: Use version with _ZEPHYR_SOURCE support

Merge in picolibc support for _ZEPHYR_SOURCE so that picolibc will
expose the Zephyr C library API.

Signed-off-by: Keith Packard <keithp@keithp.com>

Author: keith-packard

west.yml

@@ -214,7 +214,7 @@ manifest:
       path: modules/lib/openthread
     - name: picolibc
       path: modules/lib/picolibc
-      revision: 93b5d5f2ad44867b60267417cd6d6250dbf68983
+      revision: dc780962322dbaf2b326305f312721ea8cf7c265
     - name: segger
       revision: 4bfaf28a11c3e5ec29badac744fab6d2f342749e
       path: modules/debug/segger