buildman: Support fetching gcc 9.2.0

This adds support to fetch gcc 9.2.0 toolchains.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Tom Rini <trini@konsulko.com>

tools/buildman/toolchain.py

@@ -490,7 +490,7 @@ class Toolchains:
         if arch == 'aarch64':
             arch = 'arm64'
         base = 'https://www.kernel.org/pub/tools/crosstool/files/bin'
-        versions = ['7.3.0', '6.4.0', '4.9.4']
+        versions = ['9.2.0', '7.3.0', '6.4.0', '4.9.4']
         links = []
         for version in versions:
             url = '%s/%s/%s/' % (base, arch, version)