qcacmn: add 'const' for 'section' in struct TGT_REG_TABLE

To fix the following compilation error:
warning: assignment discards ‘const’
qualifier from pointer target type, at:
reg_table->section = ar6320v2_reg_table
in ol_fw.c.

It's because the register table is a
const array, while reg_table->section does
not point to a const.
So add 'const' for 'section'.

Change-Id: Idfef358817241e73d660d2730b74c2ca88e23af1
CRs-Fixed: 2017786

hif/inc/regtable_pcie.h

@@ -740,7 +740,7 @@ struct tgt_reg_section {
 };
 
 struct tgt_reg_table {
-	struct tgt_reg_section *section;
+	const struct tgt_reg_section *section;
 	uint32_t section_size;
 };