Make the PIC macro confuse the type checker less

[xchapron-ledger]

See LedgerHQ/nanox-secure-sdk#13

[xchapron-ledger]

@Ericson2314 in LedgerHQ/nanox-secure-sdk#13 your are proposing to change PIC macro to:
#define PIC(x) ((typeof(x)) pic((void *)x))
Sadly this is raising issue on many apps.
For example for app with code like: https://github.com/LedgerHQ/app-boilerplate/blob/c46ba042298e06bb7b168d375398fdb0cca51823/src/handler/get_app_name.c#L28-L34
This lead to build issue:

[CC]   build/nanox/obj/get_app_name.o
src/handler/get_app_name.c:32:42: error: used type 'typeof ("my_app")' (aka 'char [7]') where arithmetic or pointer type is required
    buffer_t rdata = {.ptr = (uint8_t *) PIC(MYAPPNAME), .size = APPNAME_LEN, .offset = 0};
                                         ^~~~~~~~~~~~~~
/home/xchapron/Workspace/LedgerHQ/ledger-secure-sdk/include/os_pic.h:10:17: note: expanded from macro 'PIC'
#define PIC(x) ((typeof(x)) pic((void *)x))
                ^           ~~~~~~~~~~~~~~
1 error generated.

This issue can be fixed by changing on app side:
buffer_t rdata = {.ptr = (uint8_t *) PIC(APPNAME), .size = APPNAME_LEN, .offset = 0};
By:
buffer_t rdata = {.ptr = (uint8_t *) PIC(&APPNAME[0]), .size = APPNAME_LEN, .offset = 0};

But requiring this is not really wanted.

Do you know another way to achieve this?