Rollup merge of #116458 - bjorn3:fix_global_asm_test, r=workingjubilee

Properly export function defined in test which uses global_asm!()

Currently the test passes with the LLVM backend as the codegen unit partitioning logic happens to place both the global_asm!() and the function which calls the function defined by the global_asm!() in the same CGU. With the Cranelift backend it breaks however as it will place all assembly in separate codegen units to be passed to an external linker.

Author: workingjubilee