[MINIOS PATCH] x86/mm: add EXPORT_SYMBOL() for `pt_base`

[Anthony PERARD <anthony.perard@xxxxxxxxxx>]

Without this, building "ioemu-stubdom" fails on Debian Buster or
Bookworm, with:

/home/osstest/build.184372.build-amd64/xen/stubdom/mini-os-x86_64-ioemu/mini-os.o:
 in function `xenfb_pv_display_init':
ungetc.c:(.text+0x43533): undefined reference to `pt_base'

Signed-off-by: Anthony PERARD <anthony.perard@xxxxxxxxxx>
---
 arch/x86/mm.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/mm.c b/arch/x86/mm.c
index 767a5f0..be1cf0c 100644
--- a/arch/x86/mm.c
+++ b/arch/x86/mm.c
@@ -57,6 +57,7 @@
 unsigned long *phys_to_machine_mapping;
 unsigned long mfn_zero;
 pgentry_t *pt_base;
+EXPORT_SYMBOL(pt_base);
 static unsigned long first_free_pfn;
 static unsigned long last_free_pfn;
 static unsigned long virt_kernel_area_end = VIRT_KERNEL_AREA;
-- 
Anthony PERARD