commonlib/bsd: Remove cb_err_t

cb_err_t was meant to be used in place of `enum cb_err` in all
situations, but the choice to use a typedef here seems to be
controversial. We should not be arbitrarily using two different
identifiers for the same thing across the codebase, so since there are
no use cases for serializing enum cb_err at the moment (which would be
the primary reason to typedef a fixed-width integer instead), remove
cb_err_t again for now.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Change-Id: Iaec36210d129db26d51f0a105d3de070c03b686b
Reviewed-on: https://review.coreboot.org/c/coreboot/+/62600
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Yu-Ping Wu <yupingso@google.com>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>

payloads/libpayload/include/fmap.h

@@ -7,6 +7,6 @@
 #include <stddef.h>
 
 /* Looks for area with |name| in FlashMap. Requires lib_sysinfo.fmap_cache. */
-cb_err_t fmap_locate_area(const char *name, size_t *offset, size_t *size);
+enum cb_err fmap_locate_area(const char *name, size_t *offset, size_t *size);
 
 #endif /* _FMAP_H */