pcie: change confused comment clearer

This comment applies to all functions below it.
It is not appropriate that called capability allocation
functions, change it into capability list management functions.

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

hw/pci/pcie.c

@@ -529,7 +529,7 @@ bool pcie_cap_is_arifwd_enabled(const PCIDevice *dev)
 }
 
 /**************************************************************************
- * pci express extended capability allocation functions
+ * pci express extended capability list management functions
  * uint16_t ext_cap_id (16 bit)
  * uint8_t cap_ver (4 bit)
  * uint16_t cap_offset (12 bit)