[XS] Change in libosmocore[master]: Correctly calculate size iofd_msgb_alloc2()

Attention is currently required from: laforge, pespin.

jolly has posted comments on this change by jolly. ( https://gerrit.osmocom.org/c/libosmocore/+/41138?usp=email )

Change subject: Correctly calculate size iofd_msgb_alloc2() ......................................................................

Patch Set 2:

(1 comment)

File src/core/osmo_io.c:

https://gerrit.osmocom.org/c/libosmocore/+/41138/comment/e92cfa28_468701a5?u... : PS2, Line 193: return msgb_alloc_headroom_c(iofd, size + headroom, headroom, "osmo_io_msgb");

static inline struct msgb *msgb_alloc_headroom_c(const void *ctx, uint16_t size, uint16_t headroom, […]

I used some casting to make it clearer that there can't be an overflow.