acinclude: move HAVE_UCLIBC handling to configure.ac; fix handling

Origin commit data
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Branch: ni/coolstream
Commit: 9f51d73d10
Author: vanhofen <vanhofen@gmx.de>
Date: 2023-01-29 (Sun, 29 Jan 2023)

Origin message was:
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- acinclude: move HAVE_UCLIBC handling to configure.ac; fix handling

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No further description and justification available within origin commit message!

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This commit was generated by Migit

acinclude.m4

@@ -480,9 +480,6 @@ elif test "$BOXTYPE" = "mipsbox"; then
 	AC_DEFINE(HAVE_MIPS_HARDWARE, 1, [building for an mipsbox])
 fi
 
-# uclibc
-AM_CONDITIONAL(HAVE_UCLIBC, test "$targetlibdir/ld-uClibc.so.0")
-
 # generic
 if test "$BOXMODEL" = "generic"; then
 	AC_DEFINE(BOXMODEL_GENERIC, 1, [generic pc])

configure.ac

@@ -516,6 +516,9 @@ else
 	HWLIB_CFLAGS="$HWLIB_CFLAGS "'-I$(top_srcdir)/lib/hardware/coolstream'
 fi
 
+# uclibc
+AM_CONDITIONAL(HAVE_UCLIBC, $CC --version | grep -q "uclibc")
+
 # hack, so that framebuffer.h does not need to be included everywhere...
 AC_DEFINE(fb_pixel_t, uint32_t, [hack, so that framebuffer.h does not need to be included everywhere...])