[clang][analyzer] Fix the false positive ArgInitializedness warning on unnamed bit-field (#145066)

For the following code in C mode: https://godbolt.org/z/3eo1MeGhe
(There is no warning in C++ mode though).
```c++
struct B {
  int i : 2;
  int : 30;  // unnamed bit-field
};

extern void consume_B(struct B);

void bitfield_B_init(void) {
  struct B b1;
  b1.i = 1; // b1 is initialized
  consume_B(b1); // FP: Passed-by-value struct argument contains uninitialized data (e.g., field: '') [core.CallAndMessage]
}
```

0 files changed, 0 insertions, 0 deletions