Allocates a SafeArray descriptor with a specified VARIANT type and number of dimensions.
_SafeArrayAllocDescriptorEx($vType, $cDims)
| $vType | VARIANT type for the SafeArray elements (e.g., $VT_VARIANT, $VT_I4). |
| $cDims | Number of dimensions for the SafeArray descriptor. |
| Success: | Pointer to the SafeArray descriptor. |
| Failure: | 0 and sets @error: 1 - Invalid number of dimensions (<= 0 or > 5). 2 - Invalid VARIANT type. 3 - DllCall failure. |