cmd/link: assume that runtime.epclntab lives in .text section

Sometimes STEXT symbols point to the first byte of .data
section, instead of the end of .text section. But, while writing
pe symbol table, we should treat them as if they belong to the
.text section. Change pe symbol table records for these symbols.

Fixes #14710

Change-Id: I1356e61aa8fa37d590d7b1677b2bac214ad0ba4e
Reviewed-on: https://go-review.googlesource.com/35272
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

src/cmd/link/internal/ld/pe.go

@@ -955,10 +955,12 @@ func writePESymTableRecords(ctxt *Link) int {
 		var value int64
 		// Note: although address of runtime.edata (type SDATA) is at the start of .bss section
 		// it still belongs to the .data section, not the .bss section.
+		// Same for runtime.epclntab (type STEXT), it belongs to .text
+		// section, not the .data section.
 		if uint64(s.Value) >= Segdata.Vaddr+Segdata.Filelen && s.Type != obj.SDATA && Linkmode == LinkExternal {
 			value = int64(uint64(s.Value) - Segdata.Vaddr - Segdata.Filelen)
 			sect = bsssect
-		} else if uint64(s.Value) >= Segdata.Vaddr {
+		} else if uint64(s.Value) >= Segdata.Vaddr && s.Type != obj.STEXT {
 			value = int64(uint64(s.Value) - Segdata.Vaddr)
 			sect = datasect
 		} else if uint64(s.Value) >= Segtext.Vaddr {