nb/intel/gm45: Deduplicate PCIEXBAR decoding

We can use `decode_pcie_bar` instead, if we make it non-static.

Change-Id: I4d005290355e30e6fdaae3e8e092891fddfbe4fc
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/44118
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
diff --git a/src/northbridge/intel/gm45/gm45.h b/src/northbridge/intel/gm45/gm45.h
index d9cfbf7..d18b3d42 100644
--- a/src/northbridge/intel/gm45/gm45.h
+++ b/src/northbridge/intel/gm45/gm45.h
@@ -433,6 +433,7 @@
 int get_blc_values(const struct blc_pwm_t **entries);
 u16 get_blc_pwm_freq_value(const char *edid_ascii_string);
 
+int decode_pcie_bar(u32 *const base, u32 *const len);
 
 #include <device/device.h>