pg_upgrade check fails on Solaris 10

Hello, hackers!

We got an error for pg_upgrade check on the branch REL_11_STABLE (commit 
40ad4202513c72f5c1beeb03e26dfbc8890770c0) on Solaris 10 because IIUC the 
argument to the sed command is not enclosed in quotation marks (see 
[1]):

$ gmake -C src/bin/pg_upgrade/ check
<...>
MAKE=gmake 
bindir="/home/buildfarm/mpolyakova/postgrespro_REL_11_STABLE/inst/bin" 
libdir="/home/buildfarm/mpolyakova/postgrespro_REL_11_STABLE/inst/lib" 
EXTRA_REGRESS_OPTS="" /bin/sh test.sh --install
test.sh: MSYS/MINGW/: not found
gmake: *** [check] Error 1
gmake: Leaving directory 
`/home/buildfarm/mpolyakova/postgrespro_REL_11_STABLE/src/bin/pg_upgrade'
$ sed: command garbled: s/

Attached diff.patch fixes the problem.

About the system: SunOS, Release 5.10, KernelID Generic_141444-09.
About the used shell: according to the manual, it comes from the package 
SUNWcsu.

Thanks to Victor Wagner for his help to investigate this issue.

[1] $ man sh
<...>
Quoting
The following characters have a special meaning to the shell and cause 
termination of a word unless quoted:
;  &  (  )  |  ^  <  >  newline  space  tab

-- 
Marina Polyakova
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company