package/go: bump to version 1.15.8

go1.15.8 (released 2021/02/04) includes fixes to the compiler, linker, runtime,
the go command, and the net/http package.

https://golang.org/doc/go1.15

Signed-off-by: Christian Stewart <christian@paral.in>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/go/go.hash

@@ -1,3 +1,3 @@
 # From https://golang.org/dl/
-sha256  8631b3aafd8ecb9244ec2ffb8a2a8b4983cf4ad15572b9801f7c5b167c1a2abc  go1.15.7.src.tar.gz
+sha256  540c0ab7781084d124991321ed1458e479982de94454a98afab6acadf38497c2  go1.15.8.src.tar.gz
 sha256	2d36597f7117c38b006835ae7f537487207d8ec407aa9d9980794b2030cbc067  LICENSE

package/go/go.mk

@@ -4,7 +4,7 @@
 #
 ################################################################################
 
-GO_VERSION = 1.15.7
+GO_VERSION = 1.15.8
 GO_SITE = https://storage.googleapis.com/golang
 GO_SOURCE = go$(GO_VERSION).src.tar.gz