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.

tests/ui/asm/x86_64/issue-96797.rs

@@ -11,7 +11,14 @@ use std::arch::global_asm;
 #[no_mangle]
 fn my_func() {}
 
-global_asm!("call_foobar: jmp {}", sym foobar);
+global_asm!("
+.globl call_foobar
+.type call_foobar,@function
+.section .text.call_foobar,\"ax\",@progbits
+call_foobar: jmp {}
+.size call_foobar, .-call_foobar
+.text
+", sym foobar);
 
 fn foobar() {}